diff --git a/src/zstring.h b/src/zstring.h
index b21cba7bf..ff2691db1 100644
--- a/src/zstring.h
+++ b/src/zstring.h
@@ -37,6 +37,7 @@
 #include <stdarg.h>
 #include <string.h>
 #include <stddef.h>
+#include <string>
 #include "tarray.h"
 #include "name.h"