diff --git a/include/hjson/hjson.h b/include/hjson/hjson.h
index 3f794a9..8fc6127 100644
--- a/include/hjson/hjson.h
+++ b/include/hjson/hjson.h
@@ -367,7 +367,7 @@ class MapProxy : public Value {
   MapProxy(Value&&);
 
 public:
-  ~MapProxy();
+  ~MapProxy() override;
   MapProxy& operator =(const MapProxy&);
   MapProxy& operator =(const Value&);
   MapProxy& operator =(Value&&);