diff --git a/MantidQt/API/CMakeLists.txt b/MantidQt/API/CMakeLists.txt
index 4146c5d0fbcf1261bf700e327fe019f25dc586bc..ef0286571281fe3cffae66bde5956ea0a1fc9023 100644
--- a/MantidQt/API/CMakeLists.txt
+++ b/MantidQt/API/CMakeLists.txt
@@ -25,6 +25,7 @@
 	src/MdPlottingCmapsProvider.cpp
 	src/MdSettings.cpp
 	src/Message.cpp
+	src/MWRunFiles.cpp
 	src/OptionsPropertyWidget.cpp
 	src/pixmaps.cpp
 	src/PlotAxis.cpp
@@ -67,6 +68,7 @@ set ( MOC_FILES
   inc/MantidQtAPI/MantidDialog.h
   inc/MantidQtAPI/MantidHelpInterface.h
   inc/MantidQtAPI/MantidWidget.h
+  inc/MantidQtAPI/MWRunFiles.h
   inc/MantidQtAPI/OptionsPropertyWidget.h
   inc/MantidQtAPI/PropertyWidget.h
   inc/MantidQtAPI/PythonRunner.h
@@ -129,9 +131,15 @@ set ( INC_FILES
 
 set ( UI_FILES
   inc/MantidQtAPI/ManageUserDirectories.ui
+  inc/MantidQtAPI/MWRunFiles.ui
   inc/MantidQtAPI/ScriptRepositoryView.ui
 )
 
+# Python unit tests
+set ( TEST_PY_FILES
+  test/MWRunFilesTest.py
+)
+
 set( TEST_FILES
    BatchAlgorithmRunnerTest.h
    FileDialogHandlerTest.h
diff --git a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWRunFiles.h b/MantidQt/API/inc/MantidQtAPI/MWRunFiles.h
similarity index 98%
rename from MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWRunFiles.h
rename to MantidQt/API/inc/MantidQtAPI/MWRunFiles.h
index 6ac6f86e7a671e852fa4506f28d17b19d59c0146..59d4fd822a378f1fbbada876c4e6ca48d08923fa 100644
--- a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWRunFiles.h
+++ b/MantidQt/API/inc/MantidQtAPI/MWRunFiles.h
@@ -2,8 +2,8 @@
 #define MANTIDQTMANTIDWIDGETS_MWRUNFILES_H_
 
 #include "ui_MWRunFiles.h"
+#include "MantidQtAPI/DllOption.h"
 #include "MantidQtAPI/MantidWidget.h"
-#include "WidgetDllOption.h"
 #include <QString>
 #include <QSettings>
 #include <QComboBox>
@@ -19,7 +19,7 @@ class IAlgorithm;
 }
 
 namespace MantidQt {
-namespace MantidWidgets {
+namespace API {
 /**
  * A class to allow the asynchronous finding of files.
  */
@@ -97,7 +97,7 @@ File change history is stored at: <https://github.com/mantidproject/mantid>
 Code Documentation is available at: <http://doxygen.mantidproject.org>
 */
 
-class EXPORT_OPT_MANTIDQT_MANTIDWIDGETS MWRunFiles : public API::MantidWidget {
+class EXPORT_OPT_MANTIDQT_API MWRunFiles : public API::MantidWidget {
   Q_OBJECT
 
   Q_PROPERTY(bool findRunFiles READ isForRunFiles WRITE isForRunFiles)
@@ -249,7 +249,7 @@ public slots:
   void findFiles();
   boost::shared_ptr<const Mantid::API::IAlgorithm> stopLiveAlgorithm();
 
-protected:
+public:
   // Method for handling drop events
   void dropEvent(QDropEvent *) override;
   // called when a drag event enters the class
diff --git a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWRunFiles.ui b/MantidQt/API/inc/MantidQtAPI/MWRunFiles.ui
similarity index 100%
rename from MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWRunFiles.ui
rename to MantidQt/API/inc/MantidQtAPI/MWRunFiles.ui
diff --git a/MantidQt/API/src/GenericDialog.cpp b/MantidQt/API/src/GenericDialog.cpp
index cfad329e99df845f41a0a7493d6cf5540c5c8d90..9069528375c6ba91d7ad8d16e4b17c311fa00cb3 100644
--- a/MantidQt/API/src/GenericDialog.cpp
+++ b/MantidQt/API/src/GenericDialog.cpp
@@ -24,10 +24,8 @@
 #include <QSignalMapper>
 #include <QFileInfo>
 #include <QDir>
-#include "MantidAPI/MultipleFileProperty.h"
 #include <QGroupBox>
 #include <climits>
-#include "MantidQtAPI/FilePropertyWidget.h"
 #include "MantidQtAPI/PropertyWidgetFactory.h"
 #include "MantidQtAPI/AlgorithmPropertiesWidget.h"
 #include "MantidQtAPI/PropertyWidget.h"
diff --git a/MantidQt/MantidWidgets/src/MWRunFiles.cpp b/MantidQt/API/src/MWRunFiles.cpp
similarity index 99%
rename from MantidQt/MantidWidgets/src/MWRunFiles.cpp
rename to MantidQt/API/src/MWRunFiles.cpp
index cca9d2599fe2bbe7af578fc12c44a35275f1f473..9abc3aa5f7d3f5c0e20da1e05a26894003562627 100644
--- a/MantidQt/MantidWidgets/src/MWRunFiles.cpp
+++ b/MantidQt/API/src/MWRunFiles.cpp
@@ -1,4 +1,4 @@
-#include "MantidQtMantidWidgets/MWRunFiles.h"
+#include "MantidQtAPI/MWRunFiles.h"
 
 #include "MantidKernel/ConfigService.h"
 #include "MantidKernel/FacilityInfo.h"
@@ -25,7 +25,7 @@
 
 using namespace Mantid::Kernel;
 using namespace Mantid::API;
-using namespace MantidQt::MantidWidgets;
+using namespace MantidQt::API;
 
 ////////////////////////////////////////////////////////////////////
 // FindFilesThread
diff --git a/MantidQt/API/test/CMakeLists.txt b/MantidQt/API/test/CMakeLists.txt
index 2107f499a80dd81a7329d4a7288f1a7a6ff7b754..eec8f0b5480651334459f34223dbcbf686a6de44 100644
--- a/MantidQt/API/test/CMakeLists.txt
+++ b/MantidQt/API/test/CMakeLists.txt
@@ -3,7 +3,7 @@ if ( CXXTEST_FOUND )
 
     include_directories ( ../../../Framework/TestHelpers/inc
                           ../../../Framework/DataObjects/inc )
-    
+
     # This variable is used within the cxxtest_add_test macro to build these helper classes into the test executable.
     # It will go out of scope at the end of this file so doesn't need un-setting
     set ( TESTHELPER_SRCS ../../../Framework/TestHelpers/src/TearDownWorld.cpp
@@ -11,9 +11,9 @@ if ( CXXTEST_FOUND )
                           ../../../Framework/TestHelpers/src/InstrumentCreationHelper.cpp
                           ../../../Framework/TestHelpers/src/WorkspaceCreationHelper.cpp
         )
-    
+
     cxxtest_add_test ( MantidQtAPITest ${TEST_FILES} )
-    target_link_libraries( MantidQtAPITest LINK_PRIVATE ${TCMALLOC_LIBRARIES_LINKTIME} 
+    target_link_libraries( MantidQtAPITest LINK_PRIVATE ${TCMALLOC_LIBRARIES_LINKTIME}
             MantidQtAPI
             API
             DataObjects
@@ -27,7 +27,11 @@ if ( CXXTEST_FOUND )
             ${GMOCK_LIBRARIES}
             ${GTEST_LIBRARIES} )
     add_dependencies( GUITests MantidQtAPITest )
-    
+
     # Add to the 'UnitTests' group in VS
     set_property( TARGET MantidQtAPITest PROPERTY FOLDER "UnitTests" )
 endif ()
+
+if ( PYUNITTEST_FOUND )
+  pyunittest_add_test (${CMAKE_CURRENT_SOURCE_DIR} MantidQtAPITest ${TEST_PY_FILES} )
+endif ()
diff --git a/MantidQt/MantidWidgets/test/MWRunFilesTest.py b/MantidQt/API/test/MWRunFilesTest.py
similarity index 89%
rename from MantidQt/MantidWidgets/test/MWRunFilesTest.py
rename to MantidQt/API/test/MWRunFilesTest.py
index fecd8cdfee82603b6a02c3ab39999cccb6fada8c..78e2ca1f00344dc423568c00626e35b9f6569f11 100644
--- a/MantidQt/MantidWidgets/test/MWRunFilesTest.py
+++ b/MantidQt/API/test/MWRunFilesTest.py
@@ -14,7 +14,7 @@ class MWRunFilesTest(unittest.TestCase):
     python interpreter"""
 
     def setUp(self):
-        self.mwrunfiles = mantidqtpython.MantidQt.MantidWidgets.MWRunFiles()
+        self.mwrunfiles = mantidqtpython.MantidQt.API.MWRunFiles()
 
     def tearDown(self):
         """ Close the created widget """
@@ -28,7 +28,7 @@ class MWRunFilesTest(unittest.TestCase):
         app.exec_()
 
     def test_creation(self):
-        self.assertTrue(isinstance(self.mwrunfiles,mantidqtpython.MantidQt.MantidWidgets.MWRunFiles), "Created object is not an instance of MWRunFiles")
+        self.assertTrue(isinstance(self.mwrunfiles,mantidqtpython.MantidQt.API.MWRunFiles), "Created object is not an instance of MWRunFiles")
 
     def test_lineedit_text(self):
         self.assertEqual(len(self.mwrunfiles.text()), 0)
diff --git a/MantidQt/CustomDialogs/inc/MantidQtCustomDialogs/LoadDialog.h b/MantidQt/CustomDialogs/inc/MantidQtCustomDialogs/LoadDialog.h
index d773bede626129dbcc32abf4517f2c1164423d55..19afc1b1469ab97cced34f6366fe05f53eca8e37 100644
--- a/MantidQt/CustomDialogs/inc/MantidQtCustomDialogs/LoadDialog.h
+++ b/MantidQt/CustomDialogs/inc/MantidQtCustomDialogs/LoadDialog.h
@@ -16,7 +16,7 @@ namespace MantidQt {
 //------------------------------------------------------------------------------
 // Mantid Forward declarations
 //------------------------------------------------------------------------------
-namespace MantidWidgets {
+namespace API {
 class MWRunFiles;
 }
 
diff --git a/MantidQt/CustomDialogs/inc/MantidQtCustomDialogs/LoadDialog.ui b/MantidQt/CustomDialogs/inc/MantidQtCustomDialogs/LoadDialog.ui
index 0d7081eefa1428394513de35b5598c509cc69ba0..685333e22a57f7b6b9f86c1196aeb3eeb864c27f 100644
--- a/MantidQt/CustomDialogs/inc/MantidQtCustomDialogs/LoadDialog.ui
+++ b/MantidQt/CustomDialogs/inc/MantidQtCustomDialogs/LoadDialog.ui
@@ -179,7 +179,7 @@
         <enum>QLayout::SetMinAndMaxSize</enum>
        </property>
        <item>
-        <widget class="MantidQt::MantidWidgets::MWRunFiles" name="fileWidget" native="true">
+        <widget class="MantidQt::API::MWRunFiles" name="fileWidget" native="true">
          <property name="sizePolicy">
           <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
            <horstretch>0</horstretch>
@@ -228,9 +228,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <resources/>
diff --git a/MantidQt/CustomDialogs/src/LoadDialog.cpp b/MantidQt/CustomDialogs/src/LoadDialog.cpp
index 82cc328ea83eba5d6579b4395bd5f5a8ad0c7d27..0489e557d7956fb3a0cb32864de6515572f15c42 100644
--- a/MantidQt/CustomDialogs/src/LoadDialog.cpp
+++ b/MantidQt/CustomDialogs/src/LoadDialog.cpp
@@ -2,7 +2,7 @@
 // Includes
 //------------------------------------------------------------------------------
 #include "MantidQtCustomDialogs/LoadDialog.h"
-#include "MantidQtMantidWidgets/MWRunFiles.h"
+#include "MantidQtAPI/MWRunFiles.h"
 #include "MantidQtAPI/AlgorithmInputHistory.h"
 // Qt
 #include <QCheckBox>
@@ -311,7 +311,7 @@ int LoadDialog::createWidgetsForProperty(const Mantid::Kernel::Property *prop,
                                          QWidget *parent) {
   using namespace Mantid::API;
   using namespace Mantid::Kernel;
-  using MantidQt::MantidWidgets::MWRunFiles;
+  using MantidQt::API::MWRunFiles;
 
   QString propName = QString::fromStdString(prop->name());
   QWidget *inputWidget(NULL);
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/DirectConvertToEnergy.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/DirectConvertToEnergy.ui
index 5972eb26dba100b41fbb7e6d4d28a62cba581896..4fc4ab9799ecdda23ea9628d61b6147d44ecdf2b 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/DirectConvertToEnergy.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/DirectConvertToEnergy.ui
@@ -113,7 +113,7 @@
                  <number>6</number>
                 </property>
                 <item>
-                 <widget class="MantidQt::MantidWidgets::MWRunFiles" name="runFiles" native="true">
+                 <widget class="MantidQt::API::MWRunFiles" name="runFiles" native="true">
                   <property name="label" stdset="0">
                    <string>Runs          </string>
                   </property>
@@ -129,7 +129,7 @@
                </layout>
               </item>
               <item>
-               <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mapFile" native="true">
+               <widget class="MantidQt::API::MWRunFiles" name="mapFile" native="true">
                 <property name="findRunFiles" stdset="0">
                  <bool>false</bool>
                 </property>
@@ -148,7 +148,7 @@
                </widget>
               </item>
               <item>
-               <widget class="MantidQt::MantidWidgets::MWRunFiles" name="whiteBeamFile" native="true">
+               <widget class="MantidQt::API::MWRunFiles" name="whiteBeamFile" native="true">
                 <property name="label" stdset="0">
                  <string>Detector Vanadium</string>
                 </property>
@@ -888,14 +888,14 @@
          </property>
          <layout class="QVBoxLayout" name="verticalLayout_31">
           <item>
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="absRunFiles" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="absRunFiles" native="true">
             <property name="label" stdset="0">
              <string>Abs Units Vanadium</string>
             </property>
            </widget>
           </item>
           <item>
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="absMapFile" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="absMapFile" native="true">
             <property name="findRunFiles" stdset="0">
              <bool>false</bool>
             </property>
@@ -914,7 +914,7 @@
            </widget>
           </item>
           <item>
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="absWhiteFile" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="absWhiteFile" native="true">
             <property name="label" stdset="0">
              <string>Detector Vanadium (Abs Units)</string>
             </property>
@@ -1309,9 +1309,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::InstrumentSelector</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabCalib.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabCalib.ui
index 7b7bd2d41555f673d37b695090aa893fc0524c11..e4d0a1c9b671e8d9bfd7ee27b5d00248b7991c99 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabCalib.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabCalib.ui
@@ -151,7 +151,7 @@
            </widget>
           </item>
           <item>
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="MWRunFiles_new_vanadium_num" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="MWRunFiles_new_vanadium_num" native="true">
             <property name="text" stdset="0">
              <string>236516</string>
             </property>
@@ -175,7 +175,7 @@
            </widget>
           </item>
           <item>
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="MWRunFiles_new_ceria_num" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="MWRunFiles_new_ceria_num" native="true">
             <property name="text" stdset="0">
              <string>241391</string>
             </property>
@@ -430,9 +430,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <resources/>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabFocus.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabFocus.ui
index a8e60152cc6943fe3424ef129e915c510a83936e..8dfd9f2a564799bb5abe84c966a4f1691a517fb2 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabFocus.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabFocus.ui
@@ -131,7 +131,7 @@
          </spacer>
         </item>
         <item>
-         <widget class="MantidQt::MantidWidgets::MWRunFiles" name="MWRunFiles_run_num" native="true">
+         <widget class="MantidQt::API::MWRunFiles" name="MWRunFiles_run_num" native="true">
           <property name="text" stdset="0">
            <string/>
           </property>
@@ -189,7 +189,7 @@
          </spacer>
         </item>
         <item>
-         <widget class="MantidQt::MantidWidgets::MWRunFiles" name="MWRunFiles_cropped_run_num" native="true">
+         <widget class="MantidQt::API::MWRunFiles" name="MWRunFiles_cropped_run_num" native="true">
           <property name="text" stdset="0">
            <string/>
           </property>
@@ -305,7 +305,7 @@
          </spacer>
         </item>
         <item>
-         <widget class="MantidQt::MantidWidgets::MWRunFiles" name="MWRunFiles_texture_run_num" native="true">
+         <widget class="MantidQt::API::MWRunFiles" name="MWRunFiles_texture_run_num" native="true">
           <property name="text" stdset="0">
            <string/>
           </property>
@@ -644,9 +644,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <resources/>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabPreproc.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabPreproc.ui
index 3e16a807eabe7ec4f2608768e46c5ef3c995ab18..6723e98dacaa217084075feb0f21d1ea9f13c354 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabPreproc.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionQtTabPreproc.ui
@@ -37,7 +37,7 @@
       </spacer>
      </item>
      <item>
-      <widget class="MantidQt::MantidWidgets::MWRunFiles" name="MWRunFiles_preproc_run_num" native="true">
+      <widget class="MantidQt::API::MWRunFiles" name="MWRunFiles_preproc_run_num" native="true">
        <property name="text" stdset="0">
         <string/>
        </property>
@@ -251,9 +251,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <resources/>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/DensityOfStates.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/DensityOfStates.ui
index 49f0e38fe22e5473a8bba11b4a80c44ef818217f..f04057a83e832d2734fa13ff7e91e0abc9888742 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/DensityOfStates.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/DensityOfStates.ui
@@ -21,7 +21,7 @@
      </property>
      <layout class="QGridLayout" name="gridLayout">
       <item row="0" column="0">
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mwInputFile" native="true">
+       <widget class="MantidQt::API::MWRunFiles" name="mwInputFile" native="true">
         <property name="sizePolicy">
          <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
           <horstretch>0</horstretch>
@@ -537,9 +537,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <tabstops>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/Elwin.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/Elwin.ui
index 58549540f082cf26e4bd0c36e20e748caa9333d3..54113cd8d662a0245a7eb30d8c423e46e32898d9 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/Elwin.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/Elwin.ui
@@ -21,7 +21,7 @@
      </property>
      <layout class="QHBoxLayout" name="horizontalLayout_16">
       <item>
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="dsInputFiles" native="true">
+       <widget class="MantidQt::API::MWRunFiles" name="dsInputFiles" native="true">
         <property name="sizePolicy">
          <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
           <horstretch>0</horstretch>
@@ -206,9 +206,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::PreviewPlot</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ILLCalibration.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ILLCalibration.ui
index 58d4b6665b3fb8d8fb5e362b892cfa0d420bab15..7cc538a72b08df981cf966d60908726e610c4e14 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ILLCalibration.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ILLCalibration.ui
@@ -27,7 +27,7 @@
      </property>
      <layout class="QHBoxLayout" name="horizontalLayout_2">
       <item>
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfRunFile" native="true">
+       <widget class="MantidQt::API::MWRunFiles" name="rfRunFile" native="true">
         <property name="label" stdset="0">
          <string>Run File</string>
         </property>
@@ -68,7 +68,7 @@
            <number>0</number>
           </property>
           <item>
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfMapFile" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="rfMapFile" native="true">
             <property name="label" stdset="0">
              <string></string>
             </property>
@@ -230,9 +230,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
    <container>1</container>
   </customwidget>
  </customwidgets>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ILLEnergyTransfer.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ILLEnergyTransfer.ui
index dde6a058d5dfb7e4a4ac2a1b0a55164eea547e1e..371f89dfd99264aae1ed5aed7316c70fb7ab66b9 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ILLEnergyTransfer.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ILLEnergyTransfer.ui
@@ -27,7 +27,7 @@
      </property>
      <layout class="QHBoxLayout" name="horizontalLayout_2">
       <item>
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfInput" native="true">
+       <widget class="MantidQt::API::MWRunFiles" name="rfInput" native="true">
         <property name="label" stdset="0">
          <string>Run File</string>
         </property>
@@ -110,7 +110,7 @@
            <number>0</number>
           </property>
           <item>
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfMapFile" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="rfMapFile" native="true">
             <property name="label" stdset="0">
              <string></string>
             </property>
@@ -197,9 +197,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
    <container>1</container>
   </customwidget>
   <customwidget>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISCalibration.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISCalibration.ui
index 86fc866cf28f9557d3164b14f881a73f347f163a..b053071a403fc0121c391a0de40c1fa473b599af 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISCalibration.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISCalibration.ui
@@ -29,7 +29,7 @@
       <item>
        <layout class="QHBoxLayout" name="loCalibInputFile">
         <item>
-         <widget class="MantidQt::MantidWidgets::MWRunFiles" name="leRunNo" native="true">
+         <widget class="MantidQt::API::MWRunFiles" name="leRunNo" native="true">
           <property name="sizePolicy">
            <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
             <horstretch>0</horstretch>
@@ -278,9 +278,9 @@
    <container>1</container>
   </customwidget>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <resources/>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISDiagnostics.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISDiagnostics.ui
index 509c838280b6ba6d840b838b57f566173f417428..1cdf319d81a3418bc057526b4c58bc417e39d428 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISDiagnostics.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISDiagnostics.ui
@@ -29,7 +29,7 @@
       <item>
        <layout class="QHBoxLayout" name="loInputFiles">
         <item>
-         <widget class="MantidQt::MantidWidgets::MWRunFiles" name="dsInputFiles" native="true">
+         <widget class="MantidQt::API::MWRunFiles" name="dsInputFiles" native="true">
           <property name="sizePolicy">
            <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
             <horstretch>0</horstretch>
@@ -203,9 +203,9 @@
    <container>1</container>
   </customwidget>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <tabstops>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISEnergyTransfer.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISEnergyTransfer.ui
index 2dcbbc5475ace3d0d91262b60d1dfaebf3783e0a..c44c5bec6e87b7d1cdef391f379f6b98826fe535 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISEnergyTransfer.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/ISISEnergyTransfer.ui
@@ -72,7 +72,7 @@
        </widget>
       </item>
       <item row="0" column="0">
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="dsRunFiles" native="true">
+       <widget class="MantidQt::API::MWRunFiles" name="dsRunFiles" native="true">
         <property name="sizePolicy">
          <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
           <horstretch>0</horstretch>
@@ -251,7 +251,7 @@
         <widget class="QWidget" name="pgMapFile">
          <layout class="QHBoxLayout" name="horizontalLayout_5">
           <item>
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="dsMapFile" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="dsMapFile" native="true">
             <property name="sizePolicy">
              <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>0</horstretch>
@@ -1002,9 +1002,9 @@
    <header>MantidQtMantidWidgets/DataSelector.h</header>
   </customwidget>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <tabstops>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectDiffractionReduction.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectDiffractionReduction.ui
index fb6ef4652ce2cc6196a32b64fe1716f05a470205..c64f84950cb981013a972629440fe03b1d60f4af 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectDiffractionReduction.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectDiffractionReduction.ui
@@ -122,7 +122,7 @@
         </widget>
        </item>
        <item row="5" column="1" colspan="2">
-        <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfCanFiles" native="true">
+        <widget class="MantidQt::API::MWRunFiles" name="rfCanFiles" native="true">
          <property name="enabled">
           <bool>false</bool>
          </property>
@@ -135,7 +135,7 @@
         </widget>
        </item>
        <item row="0" column="0" colspan="3">
-        <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfSampleFiles" native="true">
+        <widget class="MantidQt::API::MWRunFiles" name="rfSampleFiles" native="true">
          <property name="sizePolicy">
           <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
            <horstretch>0</horstretch>
@@ -199,7 +199,7 @@
             <number>6</number>
            </property>
            <item row="4" column="0" colspan="2">
-            <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfVanadiumFile" native="true">
+            <widget class="MantidQt::API::MWRunFiles" name="rfVanadiumFile" native="true">
              <property name="enabled">
               <bool>true</bool>
              </property>
@@ -241,7 +241,7 @@
             </widget>
            </item>
            <item row="3" column="0" colspan="2">
-            <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfCalFile" native="true">
+            <widget class="MantidQt::API::MWRunFiles" name="rfCalFile" native="true">
              <property name="minimumSize">
               <size>
                <width>0</width>
@@ -297,7 +297,7 @@
             </widget>
            </item>
            <item row="1" column="0" colspan="2">
-            <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfCalFile_only" native="true">
+            <widget class="MantidQt::API::MWRunFiles" name="rfCalFile_only" native="true">
              <property name="enabled">
               <bool>false</bool>
              </property>
@@ -680,9 +680,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::IndirectInstrumentConfig</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectLoadILL.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectLoadILL.ui
index 4aa9c8138798f3102a2770d442e7a504b609659f..2dba4d73ee7fefe8fbfade5e5c5af4877280b40a 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectLoadILL.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectLoadILL.ui
@@ -15,7 +15,7 @@
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
    <item>
-    <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mwRun">
+    <widget class="MantidQt::API::MWRunFiles" name="mwRun">
      <property name="sizePolicy">
       <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
        <horstretch>0</horstretch>
@@ -64,7 +64,7 @@
       </widget>
      </item>
      <item row="0" column="1">
-      <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mwMapFile">
+      <widget class="MantidQt::API::MWRunFiles" name="mwMapFile">
        <property name="enabled">
         <bool>false</bool>
        </property>
@@ -186,9 +186,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::IndirectInstrumentConfig</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectMolDyn.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectMolDyn.ui
index 45254f92afe4ba701ab4d04d82dd264edd16150c..0e1613f4da01d8e4c0d4299aa3fee547df50d3da 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectMolDyn.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectMolDyn.ui
@@ -28,7 +28,7 @@
        </widget>
       </item>
       <item row="1" column="1">
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mwRun" native="true">
+       <widget class="MantidQt::API::MWRunFiles" name="mwRun" native="true">
         <property name="sizePolicy">
          <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
           <horstretch>0</horstretch>
@@ -355,9 +355,9 @@
    <header>MantidQtMantidWidgets/DataSelector.h</header>
   </customwidget>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <tabstops>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectSassena.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectSassena.ui
index fc54263c1dc63d58d5b34fcc59e23bf8ac83de71..bbc63eb15aa3ab1083bcdeafb3a317bbd6aed6df 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectSassena.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/IndirectSassena.ui
@@ -24,7 +24,7 @@
        <number>6</number>
       </property>
       <item row="0" column="1">
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mwInputFile" native="true">
+       <widget class="MantidQt::API::MWRunFiles" name="mwInputFile" native="true">
         <property name="sizePolicy">
          <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
           <horstretch>0</horstretch>
@@ -156,9 +156,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <tabstops>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/Quasi.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/Quasi.ui
index 3518f75b4bb259bd77bd15219bde318fa978c3cd..77bb3a92221337cd5e37acecd893f2632a8a22f4 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/Quasi.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Indirect/Quasi.ui
@@ -137,7 +137,7 @@
          </widget>
         </item>
         <item row="1" column="1">
-         <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mwFixWidthDat" native="true">
+         <widget class="MantidQt::API::MWRunFiles" name="mwFixWidthDat" native="true">
           <property name="enabled">
            <bool>false</bool>
           </property>
@@ -405,9 +405,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::DataSelector</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/ALCDataLoadingView.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/ALCDataLoadingView.ui
index 3435fb44fa92a393a93b16f1e75caef7e0d7167d..eb60fe4880cd9e373f8f0ab178a4bee9042e9196 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/ALCDataLoadingView.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/ALCDataLoadingView.ui
@@ -50,7 +50,7 @@
              </widget>
             </item>
             <item row="1" column="1">
-             <widget class="MantidQt::MantidWidgets::MWRunFiles" name="lastRun" native="true">
+             <widget class="MantidQt::API::MWRunFiles" name="lastRun" native="true">
               <property name="sizePolicy">
                <sizepolicy hsizetype="Expanding" vsizetype="Preferred">
                 <horstretch>0</horstretch>
@@ -76,7 +76,7 @@
              </widget>
             </item>
             <item row="0" column="1">
-             <widget class="MantidQt::MantidWidgets::MWRunFiles" name="firstRun" native="true">
+             <widget class="MantidQt::API::MWRunFiles" name="firstRun" native="true">
               <property name="sizePolicy">
                <sizepolicy hsizetype="Expanding" vsizetype="Preferred">
                 <horstretch>0</horstretch>
@@ -158,7 +158,7 @@
           <item>
            <layout class="QHBoxLayout" name="horizontalLayoutDeadTime_2">
             <item>
-             <widget class="MantidQt::MantidWidgets::MWRunFiles" name="deadTimeFile" native="true">
+             <widget class="MantidQt::API::MWRunFiles" name="deadTimeFile" native="true">
               <property name="enabled">
                <bool>false</bool>
               </property>
@@ -523,9 +523,9 @@
    <container>1</container>
   </customwidget>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::LogValueSelector</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/MuonAnalysis.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/MuonAnalysis.ui
index 9c5ee1dd222a32c26a0517919c1840414bb85e54..5a9dba7224c02c339dbdad21fc46e66dca589fd9 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/MuonAnalysis.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/MuonAnalysis.ui
@@ -195,7 +195,7 @@ p, li { white-space: pre-wrap; }
                   </widget>
                  </item>
                  <item row="4" column="1">
-                  <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mwRunDeadTimeFile" native="true">
+                  <widget class="MantidQt::API::MWRunFiles" name="mwRunDeadTimeFile" native="true">
                    <property name="enabled">
                     <bool>true</bool>
                    </property>
@@ -526,7 +526,7 @@ p, li { white-space: pre-wrap; }
                <item>
                 <layout class="QHBoxLayout" name="fileInputLayout">
                  <item>
-                  <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mwRunFiles" native="true">
+                  <widget class="MantidQt::API::MWRunFiles" name="mwRunFiles" native="true">
                    <property name="sizePolicy">
                     <sizepolicy hsizetype="Expanding" vsizetype="Minimum">
                      <horstretch>0</horstretch>
@@ -534,7 +534,7 @@ p, li { white-space: pre-wrap; }
                     </sizepolicy>
                    </property>
                    <property name="toolTip">
-                    <string>Specify a run number or data file by typing a run number or use 
+                    <string>Specify a run number or data file by typing a run number or use
 the Browse button to select</string>
                    </property>
                    <property name="findRunFiles" stdset="0">
@@ -1159,19 +1159,19 @@ p, li { white-space: pre-wrap; }
              <row/>
              <column>
               <property name="text">
-               <string>Group Pair 
+               <string>Group Pair
 (Name)</string>
               </property>
              </column>
              <column>
               <property name="text">
-               <string>Forward 
+               <string>Forward
 (Group name)</string>
               </property>
              </column>
              <column>
               <property name="text">
-               <string>Backward 
+               <string>Backward
 (Group name)</string>
               </property>
              </column>
@@ -1379,7 +1379,7 @@ p, li { white-space: pre-wrap; }
        <attribute name="toolTip">
         <string>The Results Table tab allows:
 ï‚· creating result(s) tables
-ï‚· selecting which instrument log values (temp, field etc) to write out alongside the fit 
+ï‚· selecting which instrument log values (temp, field etc) to write out alongside the fit
      parameters
 ï‚· option to write out fit information from one or several data files</string>
        </attribute>
@@ -1490,9 +1490,9 @@ p, li { white-space: pre-wrap; }
              <item row="0" column="1">
               <widget class="QCheckBox" name="selectAllFittingResults">
                <property name="toolTip">
-                <string>If checked then the fit results 
-from all the runs listed are 
-selected and written to the 
+                <string>If checked then the fit results
+from all the runs listed are
+selected and written to the
 results table.</string>
                </property>
                <property name="text">
@@ -2669,9 +2669,9 @@ p, li { white-space: pre-wrap; }
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::InstrumentSelector</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/MuonSequentialFitDialog.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/MuonSequentialFitDialog.ui
index ce0433dfafbd1fd20fa7c4406d6d65805c94806d..f76871a008f68ae674e91b8c649d2455a97a88fe 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/MuonSequentialFitDialog.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/Muon/MuonSequentialFitDialog.ui
@@ -35,7 +35,7 @@
       <number>6</number>
      </property>
      <item row="0" column="1">
-      <widget class="MantidQt::MantidWidgets::MWRunFiles" name="runs" native="true">
+      <widget class="MantidQt::API::MWRunFiles" name="runs" native="true">
        <property name="label" stdset="0">
         <string/>
        </property>
@@ -257,9 +257,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <resources/>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/SANSRunWindow.h b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/SANSRunWindow.h
index 6b984b4852a973cf2c3261447c7c6521327c4159..2d6fa9ab13fde2862a0e6bf2dfeb08f9ab2669bb 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/SANSRunWindow.h
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/SANSRunWindow.h
@@ -159,7 +159,7 @@ private:
   void appendRowToMaskTable(const QString &type, const QString &detector,
                             const QString &details);
   void readNumberOfEntries(const QString &RunStep,
-                           MantidWidgets::MWRunFiles *const output);
+                           API::MWRunFiles *const output);
   QString readUserFileGUIChanges(const States type);
   QString readSampleObjectGUIChanges();
   /// Get the component distances
@@ -197,11 +197,9 @@ private:
   bool runAssign(int key, QString &logs);
   /// Load a scatter sample file or can run via Python objects using the passed
   /// Python command
-  bool assignDetBankRun(MantidWidgets::MWRunFiles &runFile,
-                        const QString &assignFn);
+  bool assignDetBankRun(API::MWRunFiles &runFile, const QString &assignFn);
   /// runs that contain only monitor counts can be direct or transmission runs
-  bool assignMonitorRun(MantidWidgets::MWRunFiles &trans,
-                        MantidWidgets::MWRunFiles &direct,
+  bool assignMonitorRun(API::MWRunFiles &trans, API::MWRunFiles &direct,
                         const QString &assignFn);
   /// Get the detectors' names
   void fillDetectNames(QComboBox *output);
@@ -361,7 +359,7 @@ private:
   /// The workspace containing the can run
   QString m_experCan;
   /// List of all run entry widgets, which are on tab page 1
-  std::vector<MantidWidgets::MWRunFiles *> m_runFiles;
+  std::vector<API::MWRunFiles *> m_runFiles;
   /// There validators are searched before a reduction begins. Where there is a
   /// problem focus goes to the widget linked to a validator whose tab is also
   /// stored in the pair. Disabling a validator QLabel disables checking that
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/SANSRunWindow.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/SANSRunWindow.ui
index 89314a94f50c6e9dff02db70e60cbe6c813aa6e1..45c4755ba0a2efea7eaae8494506990953f36217 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/SANSRunWindow.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/SANSRunWindow.ui
@@ -382,7 +382,7 @@
                 </property>
                 <layout class="QGridLayout" name="gridLayout_10">
                  <item row="0" column="0">
-                  <widget class="MantidQt::MantidWidgets::MWRunFiles" name="scatterSample" native="true">
+                  <widget class="MantidQt::API::MWRunFiles" name="scatterSample" native="true">
                    <property name="toolTip">
                     <string>The run with the sample under investigation</string>
                    </property>
@@ -398,7 +398,7 @@
                   </widget>
                  </item>
                  <item row="1" column="0">
-                  <widget class="MantidQt::MantidWidgets::MWRunFiles" name="scatCan" native="true">
+                  <widget class="MantidQt::API::MWRunFiles" name="scatCan" native="true">
                    <property name="toolTip">
                     <string>The run with the sample under investigation</string>
                    </property>
@@ -439,7 +439,7 @@
                 </property>
                 <layout class="QGridLayout" name="gridLayout_11">
                  <item row="0" column="0">
-                  <widget class="MantidQt::MantidWidgets::MWRunFiles" name="transmis" native="true">
+                  <widget class="MantidQt::API::MWRunFiles" name="transmis" native="true">
                    <property name="toolTip">
                     <string>The run with the sample under investigation</string>
                    </property>
@@ -458,7 +458,7 @@
                   </widget>
                  </item>
                  <item row="1" column="0">
-                  <widget class="MantidQt::MantidWidgets::MWRunFiles" name="transCan" native="true">
+                  <widget class="MantidQt::API::MWRunFiles" name="transCan" native="true">
                    <property name="toolTip">
                     <string>The run with the sample under investigation</string>
                    </property>
@@ -499,7 +499,7 @@
                 </property>
                 <layout class="QGridLayout" name="gridLayout_12">
                  <item row="0" column="0">
-                  <widget class="MantidQt::MantidWidgets::MWRunFiles" name="direct" native="true">
+                  <widget class="MantidQt::API::MWRunFiles" name="direct" native="true">
                    <property name="toolTip">
                     <string>The run with the sample under investigation</string>
                    </property>
@@ -518,7 +518,7 @@
                   </widget>
                  </item>
                  <item row="1" column="0">
-                  <widget class="MantidQt::MantidWidgets::MWRunFiles" name="dirCan" native="true">
+                  <widget class="MantidQt::API::MWRunFiles" name="dirCan" native="true">
                    <property name="toolTip">
                     <string>The run with the sample under investigation</string>
                    </property>
@@ -792,8 +792,8 @@
               <widget class="QCheckBox" name="saveNex_check">
                <property name="toolTip">
                 <string>Select one or more file formats.
- The Nexus format can be used to save 1D and 2D data. 
-Consider using NxCanSAS format since this can be 
+ The Nexus format can be used to save 1D and 2D data.
+Consider using NxCanSAS format since this can be
  imported into SasView.</string>
                </property>
                <property name="text">
@@ -882,7 +882,7 @@ Zero Error</string>
              <item row="3" column="2">
               <widget class="QCheckBox" name="saveNXcanSAS_check">
                <property name="toolTip">
-                <string>Select one or more file formats. 
+                <string>Select one or more file formats.
 The NXcanSAS format can be used to save 1D and 2D data. </string>
                </property>
                <property name="text">
@@ -1847,7 +1847,7 @@ intermediate ranges are there for comparison</string>
               </widget>
              </item>
              <item>
-              <widget class="MantidQt::MantidWidgets::MWRunFiles" name="floodRearFile" native="true">
+              <widget class="MantidQt::API::MWRunFiles" name="floodRearFile" native="true">
                <property name="findRunFiles" stdset="0">
                 <bool>false</bool>
                </property>
@@ -1877,7 +1877,7 @@ intermediate ranges are there for comparison</string>
               </widget>
              </item>
              <item>
-              <widget class="MantidQt::MantidWidgets::MWRunFiles" name="floodFrontFile" native="true">
+              <widget class="MantidQt::API::MWRunFiles" name="floodFrontFile" native="true">
                <property name="findRunFiles" stdset="0">
                 <bool>false</bool>
                </property>
@@ -3715,7 +3715,7 @@ p, li { white-space: pre-wrap; }
                     <item>
                      <widget class="QLabel" name="label_14">
                       <property name="text">
-                       <string>Tolerance 
+                       <string>Tolerance
 [um]</string>
                       </property>
                       <property name="alignment">
@@ -4409,7 +4409,7 @@ p, li { white-space: pre-wrap; }
            <number>6</number>
           </property>
           <item row="0" column="0">
-           <widget class="MantidQt::MantidWidgets::MWRunFiles" name="file_run_edit" native="true">
+           <widget class="MantidQt::API::MWRunFiles" name="file_run_edit" native="true">
             <property name="sizePolicy">
              <sizepolicy hsizetype="MinimumExpanding" vsizetype="Minimum">
               <horstretch>0</horstretch>
@@ -4667,9 +4667,9 @@ p, li { white-space: pre-wrap; }
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::MessageDisplay</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/StepScan.ui b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/StepScan.ui
index 0d418b6b63db50702e1c583152f908ab1d4d104c..3eb2dd0adeca30ae425867e53cbe120a2f666ea8 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/StepScan.ui
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/StepScan.ui
@@ -18,7 +18,7 @@
    <item row="0" column="0">
     <layout class="QHBoxLayout" name="horizontalLayout">
      <item>
-      <widget class="MantidQt::MantidWidgets::MWRunFiles" name="mWRunFiles">
+      <widget class="MantidQt::API::MWRunFiles" name="mWRunFiles">
        <property name="label" stdset="0">
         <string>Data source</string>
        </property>
@@ -29,7 +29,7 @@
         <bool>true</bool>
        </property>
        <property name="buttonOpt" stdset="0">
-        <enum>MantidQt::MantidWidgets::MWRunFiles::Text</enum>
+        <enum>MantidQt::API::MWRunFiles::Text</enum>
        </property>
        <property name="fileExtensions">
         <stringlist>
@@ -37,7 +37,7 @@
         </stringlist>
        </property>
        <property name="liveButton" stdset="0">
-        <enum>MantidQt::MantidWidgets::MWRunFiles::Show</enum>
+        <enum>MantidQt::API::MWRunFiles::Show</enum>
        </property>
       </widget>
      </item>
@@ -356,9 +356,9 @@ p, li { white-space: pre-wrap; }
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::WorkspaceSelector</class>
diff --git a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/UserInputValidator.h b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/UserInputValidator.h
index a069c28acb4d0577b0f63b1817b34ea803f2736e..0fe5b0369a31cf6404e2ebd3ddb35752d3063e02 100644
--- a/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/UserInputValidator.h
+++ b/MantidQt/CustomInterfaces/inc/MantidQtCustomInterfaces/UserInputValidator.h
@@ -2,11 +2,11 @@
 #define MANTID_CUSTOMINTERFACES_USERINPUTVALIDATOR_H_
 
 #include "MantidQtMantidWidgets/WorkspaceSelector.h"
-#include "MantidQtMantidWidgets/MWRunFiles.h"
+#include "MantidQtAPI/MWRunFiles.h"
 #include "MantidQtMantidWidgets/DataSelector.h"
 
+using MantidQt::API::MWRunFiles;
 using MantidQt::MantidWidgets::WorkspaceSelector;
-using MantidQt::MantidWidgets::MWRunFiles;
 using MantidQt::MantidWidgets::DataSelector;
 
 class QLineEdit;
diff --git a/MantidQt/CustomInterfaces/src/EnggDiffraction/EnggDiffractionViewQtGUI.cpp b/MantidQt/CustomInterfaces/src/EnggDiffraction/EnggDiffractionViewQtGUI.cpp
index fa97dab139e1c64d11e79b77f6815166429c8dfa..ae30702477911ede138409d12d6adbc0a2846e23 100644
--- a/MantidQt/CustomInterfaces/src/EnggDiffraction/EnggDiffractionViewQtGUI.cpp
+++ b/MantidQt/CustomInterfaces/src/EnggDiffraction/EnggDiffractionViewQtGUI.cpp
@@ -4,7 +4,7 @@
 #include "MantidQtAPI/AlgorithmRunner.h"
 #include "MantidQtAPI/HelpWindow.h"
 #include "MantidQtCustomInterfaces/EnggDiffraction/EnggDiffractionPresenter.h"
-#include "MantidQtMantidWidgets/MWRunFiles.h"
+#include "MantidQtAPI/MWRunFiles.h"
 
 #include <Poco/DirectoryIterator.h>
 #include <Poco/Path.h>
diff --git a/MantidQt/CustomInterfaces/src/SANSRunWindow.cpp b/MantidQt/CustomInterfaces/src/SANSRunWindow.cpp
index 60ce16f466481540d42e047133020486ebbb37de..df1fffbc1391524690ecbcec3636e40ffae2aacb 100644
--- a/MantidQt/CustomInterfaces/src/SANSRunWindow.cpp
+++ b/MantidQt/CustomInterfaces/src/SANSRunWindow.cpp
@@ -2177,8 +2177,8 @@ bool SANSRunWindow::handleLoadButtonClick() {
 *  @param RunStep name of the RunStep Python object
 *  @param output where the number will be displayed
 */
-void SANSRunWindow::readNumberOfEntries(
-    const QString &RunStep, MantidWidgets::MWRunFiles *const output) {
+void SANSRunWindow::readNumberOfEntries(const QString &RunStep,
+                                        API::MWRunFiles *const output) {
   QString periods = runReduceScriptFunction("print i.ReductionSingleton()." +
                                             RunStep + ".periods_in_file");
   output->setNumberOfEntries(periods.toInt());
@@ -3412,8 +3412,8 @@ void SANSRunWindow::resetDefaultOutput(const QString &wsName) {
 * present) file
 *  @param assignFn this is different for can or sample
 */
-bool SANSRunWindow::assignMonitorRun(MantidWidgets::MWRunFiles &trans,
-                                     MantidWidgets::MWRunFiles &direct,
+bool SANSRunWindow::assignMonitorRun(API::MWRunFiles &trans,
+                                     API::MWRunFiles &direct,
                                      const QString &assignFn) {
   // need something to place between names printed by Python that won't be
   // intepreted as the names or removed as white space
@@ -3461,7 +3461,7 @@ bool SANSRunWindow::assignMonitorRun(MantidWidgets::MWRunFiles &trans,
  * @param[in] assignFn the Python command to run
  * @return true if there were no Python errors, false otherwise
  */
-bool SANSRunWindow::assignDetBankRun(MantidWidgets::MWRunFiles &runFile,
+bool SANSRunWindow::assignDetBankRun(API::MWRunFiles &runFile,
                                      const QString &assignFn) {
   // need something to place between names printed by Python that won't be
   // intepreted as the names or removed as white space
diff --git a/MantidQt/DesignerPlugins/inc/MantidQtDesignerPlugins/PluginCollectionInterface.h b/MantidQt/DesignerPlugins/inc/MantidQtDesignerPlugins/PluginCollectionInterface.h
index 35099a9826e15ccf8296cc26533dd41074860f5c..860f4dd1f0c5c021e96bc68ccfff4a539eb67658 100644
--- a/MantidQt/DesignerPlugins/inc/MantidQtDesignerPlugins/PluginCollectionInterface.h
+++ b/MantidQt/DesignerPlugins/inc/MantidQtDesignerPlugins/PluginCollectionInterface.h
@@ -7,7 +7,7 @@
 #include "MantidQtMantidWidgets/DataSelector.h"
 #include "MantidQtDesignerPlugins/DesignerPlugin.h"
 #include "MantidQtMantidWidgets/ScriptEditor.h"
-#include "MantidQtMantidWidgets/MWRunFiles.h"
+#include "MantidQtAPI/MWRunFiles.h"
 #include "MantidQtMantidWidgets/FitPropertyBrowser.h"
 #include "MantidQtMantidWidgets/MuonFitPropertyBrowser.h"
 #include "MantidQtMantidWidgets/InstrumentSelector.h"
@@ -97,7 +97,7 @@ DECLARE_WIDGET_PLUGIN(AlgorithmSelectorWidgetPlugin,
 DECLARE_WIDGET_PLUGIN(ScriptEditorPlugin, ScriptEditor,
                       "Widget for editing python script");
 
-DECLARE_WIDGET_PLUGIN(FileFinderPlugin, MantidQt::MantidWidgets::MWRunFiles,
+DECLARE_WIDGET_PLUGIN(FileFinderPlugin, MantidQt::API::MWRunFiles,
                       "Searches for the given files within the paths defined "
                       "by\nMantid's datasearch.directories property");
 
diff --git a/MantidQt/MantidWidgets/CMakeLists.txt b/MantidQt/MantidWidgets/CMakeLists.txt
index e8e15d5862eec33acfe303e23f082c2481c26c9f..6c6e52886f85da05d7224722b196aa892921f4e8 100644
--- a/MantidQt/MantidWidgets/CMakeLists.txt
+++ b/MantidQt/MantidWidgets/CMakeLists.txt
@@ -85,7 +85,6 @@ set ( SRC_FILES
 	src/LineEditWithClear.cpp
 	src/LogValueSelector.cpp
 	src/MWDiag.cpp
-	src/MWRunFiles.cpp
 	src/MWView.cpp
 	src/MantidHelpWindow.cpp
 	src/MantidSurfacePlotDialog.cpp
@@ -126,7 +125,7 @@ set ( SRC_FILES
 )
 
 # Header files with Q_OBJECT that qmake will "moc"
-set ( MOC_FILES 
+set ( MOC_FILES
     inc/MantidQtMantidWidgets/AlgorithmSelectorWidget.h
     inc/MantidQtMantidWidgets/CheckboxHeader.h
     inc/MantidQtMantidWidgets/ColorBarWidget.h
@@ -163,7 +162,6 @@ set ( MOC_FILES
     inc/MantidQtMantidWidgets/MuonFitPropertyBrowser.h
     inc/MantidQtMantidWidgets/MuonFunctionBrowser.h
     inc/MantidQtMantidWidgets/MWDiag.h
-    inc/MantidQtMantidWidgets/MWRunFiles.h
     inc/MantidQtMantidWidgets/MWView.h
     inc/MantidQtMantidWidgets/PeakPicker.h
     inc/MantidQtMantidWidgets/PeriodicTableWidget.h
@@ -327,7 +325,7 @@ set ( INC_FILES
 )
 
 # QtDesigner UI files to process
-set ( UI_FILES 
+set ( UI_FILES
     inc/MantidQtMantidWidgets/DataProcessorUI/DataProcessorOptionsDialog.ui
     inc/MantidQtMantidWidgets/DataProcessorUI/DataProcessorWidget.ui
     inc/MantidQtMantidWidgets/DataSelector.ui
@@ -338,7 +336,6 @@ set ( UI_FILES
     inc/MantidQtMantidWidgets/IndirectInstrumentConfig.ui
 	inc/MantidQtMantidWidgets/LogValueSelector.ui
     inc/MantidQtMantidWidgets/MWDiag.ui
-    inc/MantidQtMantidWidgets/MWRunFiles.ui
     inc/MantidQtMantidWidgets/MWView.ui
     inc/MantidQtMantidWidgets/MultifitSetupDialog.ui
     inc/MantidQtMantidWidgets/MuonFitDataSelector.ui
@@ -355,11 +352,6 @@ set ( UI_FILES
     inc/MantidQtMantidWidgets/InstrumentView/UCorrectionDialog.ui
 )
 
-# Python unit tests
-set ( TEST_PY_FILES
-  test/MWRunFilesTest.py
-)
-
 set ( TEST_FILES
 	AlgorithmHintStrategyTest.h
 	TrackedActionTest.h
@@ -393,7 +385,7 @@ qt4_wrap_cpp ( MOCCED_FILES ${MOC_FILES} )
 
 set ( ALL_SRC ${SRC_FILES} ${MOCCED_FILES} )
 
-qt4_wrap_ui ( UI_HDRS ${UI_FILES} ) 
+qt4_wrap_ui ( UI_HDRS ${UI_FILES} )
 qt4_add_resources ( RES_FILES ${PROJECT_SOURCE_DIR}/images/MantidWidgets.qrc )
 
 include_directories ( ${QSCINTILLA_INCLUDE_DIR} )
@@ -412,7 +404,7 @@ if (OSX_VERSION VERSION_GREATER 10.8)
   set_target_properties ( MantidWidgets PROPERTIES INSTALL_RPATH "@loader_path/../MacOS")
 endif ()
 
-target_link_libraries ( MantidWidgets LINK_PRIVATE ${TCMALLOC_LIBRARIES_LINKTIME} 
+target_link_libraries ( MantidWidgets LINK_PRIVATE ${TCMALLOC_LIBRARIES_LINKTIME}
             MantidQtAPI
             QtPropertyBrowser
             ${CORE_MANTIDLIBS}
diff --git a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/DataSelector.h b/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/DataSelector.h
index 63ca54e5b9dbf8b6e40fa4309cbee17bc7fd10a7..6a4c863a2ec5c001407901d798e375909caad368 100644
--- a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/DataSelector.h
+++ b/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/DataSelector.h
@@ -12,8 +12,8 @@
 namespace MantidQt {
 namespace MantidWidgets {
 
-using ButtonOpts = MWRunFiles::ButtonOpts;
-using LiveButtonOpts = MWRunFiles::LiveButtonOpts;
+using ButtonOpts = API::MWRunFiles::ButtonOpts;
+using LiveButtonOpts = API::MWRunFiles::LiveButtonOpts;
 
 /**
 This class defines a widget for selecting a workspace of file path by using a
diff --git a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/DataSelector.ui b/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/DataSelector.ui
index bf3851e6db163a01bee74fc633da23e3e2eb9ba0..0c377292159ce19bbc6d3db604e73bfdaac554d3 100644
--- a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/DataSelector.ui
+++ b/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/DataSelector.ui
@@ -48,7 +48,7 @@
         <number>0</number>
        </property>
        <item>
-        <widget class="MantidQt::MantidWidgets::MWRunFiles" name="rfFileInput" native="true">
+        <widget class="MantidQt::API::MWRunFiles" name="rfFileInput" native="true">
          <property name="label" stdset="0">
           <string/>
          </property>
@@ -101,9 +101,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
   <customwidget>
    <class>MantidQt::MantidWidgets::WorkspaceSelector</class>
diff --git a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWDiag.ui b/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWDiag.ui
index d673e5af0a836359b75fb78d00d2dfe0a9229381..6b482e6d48d4cc344df276bcf9ac6aca7b4711e0 100644
--- a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWDiag.ui
+++ b/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MWDiag.ui
@@ -20,7 +20,7 @@
    <item>
     <layout class="QHBoxLayout" name="horizontalLayout">
      <item>
-      <widget class="MantidQt::MantidWidgets::MWRunFiles" name="maskFileFinder">
+      <widget class="MantidQt::API::MWRunFiles" name="maskFileFinder">
        <property name="toolTip">
         <string>A file containing a list of spectra numbers which we aleady know should be masked</string>
        </property>
@@ -158,7 +158,7 @@
      </property>
      <layout class="QVBoxLayout" name="verticalLayout">
       <item>
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="white_file">
+       <widget class="MantidQt::API::MWRunFiles" name="white_file">
         <property name="label" stdset="0">
          <string>Detector Van 1</string>
         </property>
@@ -228,7 +228,7 @@
      </property>
      <layout class="QVBoxLayout" name="verticalLayout_2">
       <item>
-       <widget class="MantidQt::MantidWidgets::MWRunFiles" name="white_file_2">
+       <widget class="MantidQt::API::MWRunFiles" name="white_file_2">
         <property name="label" stdset="0">
          <string>Detector Van 2</string>
         </property>
@@ -421,9 +421,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <resources/>
diff --git a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MuonFitDataSelector.ui b/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MuonFitDataSelector.ui
index eb826e22440ffea9cb7e517befad50cc3e76c6d2..c889629f62a539fc5dbf15890af182410ae221a9 100644
--- a/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MuonFitDataSelector.ui
+++ b/MantidQt/MantidWidgets/inc/MantidQtMantidWidgets/MuonFitDataSelector.ui
@@ -38,7 +38,7 @@
               </widget>
              </item>
              <item>
-              <widget class="MantidQt::MantidWidgets::MWRunFiles" name="runs" native="true">
+              <widget class="MantidQt::API::MWRunFiles" name="runs" native="true">
                <property name="sizePolicy">
                 <sizepolicy hsizetype="Expanding" vsizetype="Preferred">
                  <horstretch>0</horstretch>
@@ -334,9 +334,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>MantidQt::MantidWidgets::MWRunFiles</class>
+   <class>MantidQt::API::MWRunFiles</class>
    <extends>QWidget</extends>
-   <header>MantidQtMantidWidgets/MWRunFiles.h</header>
+   <header>MantidQtAPI/MWRunFiles.h</header>
   </customwidget>
  </customwidgets>
  <resources/>
diff --git a/MantidQt/MantidWidgets/src/MWDiag.cpp b/MantidQt/MantidWidgets/src/MWDiag.cpp
index a832a84b69149bbc34ced9d3a2c15afb6b5faee2..346a19a16e7789f55b90f1ee45de918fb808924b 100644
--- a/MantidQt/MantidWidgets/src/MWDiag.cpp
+++ b/MantidQt/MantidWidgets/src/MWDiag.cpp
@@ -1,6 +1,6 @@
 #include "MantidQtMantidWidgets/MWDiag.h"
 #include "MantidQtMantidWidgets/DiagResults.h"
-#include "MantidQtMantidWidgets/MWRunFiles.h"
+#include "MantidQtAPI/MWRunFiles.h"
 #include "MantidQtAPI/AlgorithmInputHistory.h"
 #include "MantidAPI/FrameworkManager.h"
 #include "MantidAPI/AnalysisDataService.h"
diff --git a/MantidQt/MantidWidgets/src/MuonFitDataSelector.cpp b/MantidQt/MantidWidgets/src/MuonFitDataSelector.cpp
index 75e4d0a9615aa0f34dd2a9d0960329ab9886828d..a19f8ec1a6b8738313ae3c00f71c2e0b39003950 100644
--- a/MantidQt/MantidWidgets/src/MuonFitDataSelector.cpp
+++ b/MantidQt/MantidWidgets/src/MuonFitDataSelector.cpp
@@ -26,7 +26,7 @@ MuonFitDataSelector::MuonFitDataSelector(QWidget *parent)
   // Disable "Browse" button - use case is that first run will always be the one
   // selected on front tab. User will type in the runs they want rather than
   // using the Browse button. (If they want to "Browse" they can use front tab).
-  m_ui.runs->doButtonOpt(MWRunFiles::ButtonOpts::None);
+  m_ui.runs->doButtonOpt(API::MWRunFiles::ButtonOpts::None);
 }
 
 /**
diff --git a/MantidQt/Python/mantidqt.sip b/MantidQt/Python/mantidqt.sip
index fc5742a3eb07377e0c3c092aaea7e22381d7851f..c0a474d5405ec6b6e1207cebcde5bfd6ccd232d9 100644
--- a/MantidQt/Python/mantidqt.sip
+++ b/MantidQt/Python/mantidqt.sip
@@ -84,7 +84,7 @@ namespace GraphOptions
   enum ScaleType {Linear, Log10};
 
   enum Axis{Left, Right, Bottom, Top};
-  
+
   enum CurveType {
   Line,
   Scatter,
@@ -194,13 +194,13 @@ public:
 
 };
 
-namespace MantidWidgets
+namespace API
 {
 
 class MWRunFiles : QWidget
 {
 %TypeHeaderCode
-#include "MantidQtMantidWidgets/MWRunFiles.h"
+#include "MantidQtAPI/MWRunFiles.h"
 %End
 public:
 void setLabelMinWidth(const int);