diff --git a/include/caosdb/status_code.h b/include/caosdb/status_code.h
index 6fb8db3eea71a34038fa347df40f9be7ccbba70e..f24ffaeddb828dc9db9c5901d42f9f413993e4bd 100644
--- a/include/caosdb/status_code.h
+++ b/include/caosdb/status_code.h
@@ -22,6 +22,8 @@
 #ifndef CAOSDB_STATUS_CODE_H
 #define CAOSDB_STATUS_CODE_H
 
+#include <string>
+
 /**
  * StatusCodes represent the status of this client, it's connections,
  * configuration and so on.