diff --git a/spec.bs b/spec.bs
index b7dad7d..108b6e5 100644
--- a/spec.bs
+++ b/spec.bs
@@ -687,6 +687,12 @@ For now, see [https://github.com/wicg/observable#operators](https://github.com/w
     1. <span class=XXX>TODO: Spec this and use |mapper|.</span>
 </div>
 
+<div algorithm>
+  The <dfn for=Observable method><code>finally(|callback|)</code></dfn> method steps are:
+
+    1. <span class=XXX>TODO: Spec this and use |callback|.</span>
+</div>
+
 
 <h4 id=promise-returning-operators>{{Promise}}-returning operators</h4>