diff --git a/Code/Mantid/Build/CMake/FindJsonCPP.cmake b/Code/Mantid/Build/CMake/FindJsonCPP.cmake
index c52d1418812beaa04c755d26d6616531f0f5fd37..a28f35fd333419710e6fd43c98b8c88ac28fbacb 100644
--- a/Code/Mantid/Build/CMake/FindJsonCPP.cmake
+++ b/Code/Mantid/Build/CMake/FindJsonCPP.cmake
@@ -9,11 +9,6 @@
 #  JSONCPP_LIBRARY_DEBUG  - library files for linking (debug version)
 #  JSONCPP_LIBRARIES      - All required libraries, including the configuration type
 
-# Using unset here is a temporary hack to force FindJson to find the correct
-# path in an incremental build. It should be removed a day or two after the
-# branch introducing this is merged.
-unset ( JSONCPP_INCLUDE_DIR CACHE )
-
 # Headers
 find_path ( JSONCPP_INCLUDE_DIR json/reader.h
             PATH_SUFFIXES jsoncpp )