diff --git a/include/cppkafka/message.h b/include/cppkafka/message.h
index 4226c093..6faeffe0 100644
--- a/include/cppkafka/message.h
+++ b/include/cppkafka/message.h
@@ -43,7 +43,7 @@
 namespace cppkafka {
 
 class MessageTimestamp;
-struct Internal;
+class Internal;
 
 /**
  * \brief Thin wrapper over a rdkafka message handle