diff --git a/include/binder/Parcel.h b/include/binder/Parcel.h
index 32c9a1d..bfe13f0 100644
--- a/include/binder/Parcel.h
+++ b/include/binder/Parcel.h
@@ -53,7 +53,8 @@
     
     status_t            setData(const uint8_t* buffer, size_t len);
 
-    status_t            appendFrom(Parcel *parcel, size_t start, size_t len);
+    status_t            appendFrom(const Parcel *parcel,
+                                   size_t start, size_t len);
 
     bool                hasFileDescriptors() const;