diff --git a/doc/macro_reference.qbk b/doc/macro_reference.qbk
index 0879a07d..9345d704 100644
--- a/doc/macro_reference.qbk
+++ b/doc/macro_reference.qbk
@@ -1535,6 +1535,13 @@ Defined if the Windows platform API is available.
 Defined if the dinkumware standard library is in use, takes the same value
 as the Dinkumware library version macro `_CPPLIB_VER` if defined, otherwise 1.
 ]]
+[[`BOOST_MSSTL_VERSION`][`<boost/config.hpp>`][
+Defined if the Microsoft Visual C++ standard library is in use.
+Has the value of `_MSVC_STL_VERSION` when that is defined, and a synthesized
+value of the same format otherwise. Example values are 143 for
+VS2022/msvc-14.3, 142 for VS2019/msvc-14.2, 141 for VS2017/msvc-14.1,
+140 for VS2015/msvc-14.0, 120 for VS2013/msvc-12.0, and so on.
+]]
 [[`BOOST_NO_WREGEX`][`<boost/regex.hpp>`][
 Defined if the regex library does not support wide character regular
 expressions.