diff --git a/README b/README
index 6dcfffd..0d4cf7d 100644
--- a/README
+++ b/README
@@ -101,6 +101,9 @@ standard output.
 is emited. If you don't specify it or set it to **-1**, it's just ignored.
 If specified, it must be a positive value. 12 is usually a good value.
 
+*lazy* when set to ``True`` will also take into account files not added to the 
+index.
+
 Also, make sure the file is executable and adapt the shebang line so it
 point to your python interpreter.