diff --git a/README.md b/README.md
index 052923e9..490fc20c 100644
--- a/README.md
+++ b/README.md
@@ -262,7 +262,7 @@ and the run command like this:
 (NB. This is only necessary if you want to work on weave. Also, these
 instructions have only been tested on Ubuntu.)
 
-To build weave you need `libpcap-dev` and `docker` installed.
+To build weave you need `libpcap-dev` and `docker` installed, and the Go SDK.
 
 Then simply run