diff --git a/README.md b/README.md
index 062badec5..b83635a31 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,7 @@ Run from source
 If you have cloned this repository to your computer, you can run OpenRefine with:
 * `./refine` on Mac OS and Linux
 * `refine.bat` on Window
+This requires JDK 8 and Ant.
 
 Documentation and Videos
 -------------------------