diff --git a/README.md b/README.md
index 21cc4d3..f540f50 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,13 @@
 # Shield
 
-Shield is a toolkit for building VPN tunnels.
+Shield is a toolkit for building VPN tunnels in Go. It does not try to
+be a full-blown VPN implementation; instead, it provides you with the
+building blocks for rolling your own.
+
+## Usage
+
+[example.go] showcases how to use the toolkit to build an unencrypted
+point-to-point tunnel. Full documentation is available at [GoDoc].
+
+[example.go]: https://github.com/ericyan/shield/blob/master/example.go
+[GoDoc]: http://godoc.org/github.com/ericyan/shield