diff --git a/pwdbased.h b/pwdbased.h
index 20828a91..a27550a7 100644
--- a/pwdbased.h
+++ b/pwdbased.h
@@ -12,6 +12,7 @@
 #include "hrtimer.h"
 #include "integer.h"
 #include "argnames.h"
+#include "algparam.h"
 #include "hmac.h"
 
 NAMESPACE_BEGIN(CryptoPP)