diff --git a/include/boost/exception/to_string.hpp b/include/boost/exception/to_string.hpp
index 871e6f4..954797f 100644
--- a/include/boost/exception/to_string.hpp
+++ b/include/boost/exception/to_string.hpp
@@ -7,6 +7,7 @@
 #define UUID_7E48761AD92811DC9011477D56D89593
 
 #include <sstream>
+#include <string>
 
 namespace
 boost