diff --git a/libcxx/docs/ReleaseNotes.rst b/libcxx/docs/ReleaseNotes.rst
--- a/libcxx/docs/ReleaseNotes.rst
+++ b/libcxx/docs/ReleaseNotes.rst
@@ -160,6 +160,11 @@
   To disable deprecation warnings you have to define ``_LIBCPP_DISABLE_DEPRECATION_WARNINGS``. Note that this
   disables all deprecation warnings.
 
+- ``_LIBCPP_ENABLE_NODISCARD`` and ``_LIBCPP_DISABLE_NODISCARD_AFTER_CXX17`` are no longer respected.
+  Any standards-required ``[[nodiscard]]`` applications in C++20 are now always enabled. Any extended applications
+  can now be enabled by defining ``_LIBCPP_ENABLE_NODISCARD_EXT``. Note that this also enables applications of
+  ``[[nodiscard]]`` in places where no version of the standard requires the attribute.
+
 ABI Changes
 -----------
 
diff --git a/libcxx/include/__config b/libcxx/include/__config
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -823,13 +823,13 @@
 
 // _LIBCPP_NODISCARD_EXT may be used to apply [[nodiscard]] to entities not
 // specified as such as an extension.
-#  if defined(_LIBCPP_ENABLE_NODISCARD) && !defined(_LIBCPP_DISABLE_NODISCARD_EXT)
+#  if defined (_LIBCPP_ENABLE_NODISCARD_EXT)
 #    define _LIBCPP_NODISCARD_EXT _LIBCPP_NODISCARD
 #  else
 #    define _LIBCPP_NODISCARD_EXT
 #  endif
 
-#  if !defined(_LIBCPP_DISABLE_NODISCARD_AFTER_CXX17) && (_LIBCPP_STD_VER > 17 || defined(_LIBCPP_ENABLE_NODISCARD))
+#  if _LIBCPP_STD_VER > 17 || defined(_LIBCPP_ENABLE_NODISCARD_EXT)
 #    define _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_NODISCARD
 #  else
 #    define _LIBCPP_NODISCARD_AFTER_CXX17