diff --git a/UnicvDbTypes.h b/UnicvDbTypes.h
index f54377a..c009358 100644
--- a/UnicvDbTypes.h
+++ b/UnicvDbTypes.h
@@ -5,6 +5,7 @@
 #include <iostream>
 #include <memory>
 #include <cstring>
+#include <string>
 
 #include "LocalFilesystem.h"