diff --git a/src/PSOEncryption.hh b/src/PSOEncryption.hh
index d56041dc..d065b510 100644
--- a/src/PSOEncryption.hh
+++ b/src/PSOEncryption.hh
@@ -3,6 +3,7 @@
 #include <inttypes.h>
 #include <stddef.h>
 
+#include <memory>
 #include <string>
 #include <vector>