diff --git a/include/internal/catch_string_manip.h b/include/internal/catch_string_manip.h
index 32a7ec1e..f7aa6d4b 100644
--- a/include/internal/catch_string_manip.h
+++ b/include/internal/catch_string_manip.h
@@ -7,13 +7,13 @@
 #ifndef TWOBLUECUBES_CATCH_STRING_MANIP_H_INCLUDED
 #define TWOBLUECUBES_CATCH_STRING_MANIP_H_INCLUDED
 
+#include "catch_stringref.h"
+
 #include <string>
 #include <iosfwd>
 
 namespace Catch {
 
-    class StringRef;
-
     bool startsWith( std::string const& s, std::string const& prefix );
     bool startsWith( std::string const& s, char prefix );
     bool endsWith( std::string const& s, std::string const& suffix );