diff --git a/CMakeLists.txt b/CMakeLists.txt
index 83cf6f4..54a0d4d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,11 +16,9 @@ option(toml11_TEST_WITH_UBSAN "use LLVM undefined behavior sanitizer" OFF)
 
 include(CheckCXXCompilerFlag)
 if("${CMAKE_VERSION}" VERSION_GREATER 3.1)
-    set(CMAKE_CXX_EXTENSIONS OFF)
-    if(NOT DEFINED CMAKE_CXX_STANDARD)
-        set(CMAKE_CXX_STANDARD 11)
-    endif()
-    set(CXX_STANDARD_REQUIRED ON)
+    set(CMAKE_CXX_STANDARD 11 CACHE STRING "The C++ standard whose features are requested to build all targets.")
+    set(CMAKE_CXX_STANDARD_REQUIRED ON CACHE BOOL "Boolean describing whether the value of CXX_STANDARD is a requirement.")
+    set(CMAKE_CXX_EXTENSIONS OFF CACHE BOOL "Boolean specifying whether compiler specific extensions are requested.")
 else()
     # Manually check for C++11 compiler flag.
     CHECK_CXX_COMPILER_FLAG("-std=c++11" COMPILER_SUPPORTS_CXX11)