diff --git a/CMakeExternals/Qwt.cmake b/CMakeExternals/Qwt.cmake
index e7a2d5c1be..d74d3356a7 100644
--- a/CMakeExternals/Qwt.cmake
+++ b/CMakeExternals/Qwt.cmake
@@ -1,39 +1,43 @@
 #-----------------------------------------------------------------------------
 # Qwt
 #-----------------------------------------------------------------------------
 
+if(MITK_USE_Qwt)
+
 # Sanity checks
 if(DEFINED Qwt_DIR AND NOT EXISTS ${Qwt_DIR})
   message(FATAL_ERROR "Qwt_DIR variable is defined but corresponds to non-existing directory")
 endif()
 
 set(proj Qwt)
 set(proj_DEPENDENCIES )
 set(${proj}_DEPENDS ${proj})
 
 if(NOT DEFINED ${proj}_DIR)
 
   set(patch_cmd ${CMAKE_COMMAND} -Dproj:STRING=${proj} -Dproj_target:STRING=qwt -P ${CMAKE_CURRENT_LIST_DIR}/GenerateDefaultCMakeBuildSystem.cmake)
 
   ExternalProject_Add(${proj}
      SOURCE_DIR ${CMAKE_BINARY_DIR}/${proj}-src
      BINARY_DIR ${proj}-build
      PREFIX ${proj}-cmake
      URL ${MITK_THIRDPARTY_DOWNLOAD_PREFIX_URL}/qwt-6.1.0.tar.bz2
      URL_MD5 aef0437b37f191067a6a9dc01c30ba64
      PATCH_COMMAND ${patch_cmd}
      INSTALL_COMMAND ""
      CMAKE_GENERATOR ${gen}
      CMAKE_ARGS
        ${ep_common_args}
        -DQT_QMAKE_EXECUTABLE:FILEPATH=${QT_QMAKE_EXECUTABLE}
      DEPENDS ${proj_DEPENDENCIES}
     )
 
   set(${proj}_DIR ${CMAKE_CURRENT_BINARY_DIR}/${proj}-build)
 
 else()
 
   mitkMacroEmptyExternalProject(${proj} "${proj_DEPENDENCIES}")
 
 endif()
+
+endif()
diff --git a/CMakeExternals/Qxt.cmake b/CMakeExternals/Qxt.cmake
index 4eeb337e23..4b31a6c901 100644
--- a/CMakeExternals/Qxt.cmake
+++ b/CMakeExternals/Qxt.cmake
@@ -1,39 +1,43 @@
 #-----------------------------------------------------------------------------
 # Qxt
 #-----------------------------------------------------------------------------
 
+if(MITK_USE_Qxt)
+
 # Sanity checks
 if(DEFINED Qxt_DIR AND NOT EXISTS ${Qxt_DIR})
   message(FATAL_ERROR "Qxt_DIR variable is defined but corresponds to non-existing directory")
 endif()
 
 set(proj Qxt)
 set(proj_DEPENDENCIES )
 set(${proj}_DEPENDS ${proj})
 
 if(NOT DEFINED ${proj}_DIR)
 
   set(patch_cmd ${CMAKE_COMMAND} -Dproj:STRING=${proj} -Dproj_target:STRING=QxtCore -P ${CMAKE_CURRENT_LIST_DIR}/GenerateDefaultCMakeBuildSystem.cmake)
 
   ExternalProject_Add(${proj}
      SOURCE_DIR ${CMAKE_BINARY_DIR}/${proj}-src
      BINARY_DIR ${proj}-build
      PREFIX ${proj}-cmake
      URL ${MITK_THIRDPARTY_DOWNLOAD_PREFIX_URL}/libqxt-0.6.2-dadc327c2a6a-patched.tar.gz
      URL_MD5 b0438b4c76793c35b606c8aba02748b8
      PATCH_COMMAND ${patch_cmd}
      INSTALL_COMMAND ""
      CMAKE_GENERATOR ${gen}
      CMAKE_ARGS
        ${ep_common_args}
        -DQT_QMAKE_EXECUTABLE:FILEPATH=${QT_QMAKE_EXECUTABLE}
      DEPENDS ${proj_DEPENDENCIES}
     )
 
   set(${proj}_DIR ${CMAKE_CURRENT_BINARY_DIR}/${proj}-build)
 
 else()
 
   mitkMacroEmptyExternalProject(${proj} "${proj_DEPENDENCIES}")
 
 endif()
+
+endif()