diff --git a/include/boost/process/v2/environment.hpp b/include/boost/process/v2/environment.hpp
index ae081d16..69bacb66 100644
--- a/include/boost/process/v2/environment.hpp
+++ b/include/boost/process/v2/environment.hpp
@@ -13,6 +13,7 @@
 #include <boost/process/v2/detail/config.hpp>
 #include <boost/process/v2/cstring_ref.hpp>
 #include <boost/process/v2/detail/utf8.hpp>
+#include <boost/type_traits.hpp>
 #include <functional>
 #include <memory>
 #include <numeric>