diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 171b5952a..4fe757984 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -51,6 +51,19 @@ email them to maintainers, or request a maintainer pull from your tree directly
 -- but note that some maintainers will be more receptive to these methods than
 others.
 
+When contributing changes, via whatever means, make sure you describe them
+appropriately.  You should attach a reasonably high-level summary of what the
+changes are and what they do; reference any useful background material that may
+exist, e.g. a GitHub issue, a mailing list discussion, a UP, etc.  [Here][jbpr]
+is a good example of a pull request with a useful, concise description.
+
+If your changes replace significant extant functionality, be sure to compare
+them with the thing you're replacing.  You may also want to cc maintainers,
+reviewers, or other parties who might have a particular interest in what you're
+contributing.
+
+[jbpr]: https://github.com/urbit/urbit/pull/1782
+
 ### Hygiene
 
 Commits should generally be relevant, atomic, and have descriptions formatted