diff --git a/README b/README
index ad232e11870304583ea213a2386af2c6e47f9e9d..088844b795747c4d75e524df3c975545c338317d 100644
--- a/README
+++ b/README
@@ -23,7 +23,7 @@ You can run a 32 bit Redis binary using:
 
     % make 32bit
 
-After you build Redis is a good idea to test it, using:
+After you build Redis is a good idea to test it (which require Tcl), using:
 
     % make test