diff --git a/SuperBuild/External_STIR.cmake b/SuperBuild/External_STIR.cmake
index 65d0d24f..3fa46e4b 100644
--- a/SuperBuild/External_STIR.cmake
+++ b/SuperBuild/External_STIR.cmake
@@ -100,7 +100,7 @@ if(NOT ( DEFINED "USE_SYSTEM_${externalProjName}" AND "${USE_SYSTEM_${externalPr
     -DCMAKE_POSITION_INDEPENDENT_CODE:BOOL=ON
     -DCMAKE_INSTALL_PREFIX:PATH=${STIR_INSTALL_DIR}
     -DGRAPHICS:STRING=None
-    -DCMAKE_CXX_STANDARD:STRING=11
+    -DCMAKE_CXX_STANDARD:STRING=14
     -DSTIR_OPENMP:BOOL=${STIR_ENABLE_OPENMP}
     -DOPENMP_INCLUDES:PATH=${OPENMP_INCLUDES}
     -DOPENMP_LIBRARIES:PATH=${OPENMP_LIBRARIES}