diff --git a/README.md b/README.md
index c522600..d4f425b 100644
--- a/README.md
+++ b/README.md
@@ -12,6 +12,8 @@ Compare a project update with its schedules, inspect what changed, and record th
 
 Northstar is synthetic. Checks cover supported schedule fields and narrative keywords; they do not establish cause, entitlement or approval.
 
+**Case study:** [The problem, review journey and before-and-after design](https://matthewpaver.github.io/work/projectlens/).
+
 **Technical evidence:** [How the checks work](#how-it-works) · [Results](#results) · [Tests](#repository-layout-and-tests) · [Run locally](#quickstart) · [Limits](#limits-and-non-goals)
 
 [![Verify and deploy](https://github.com/MatthewPaver/ProjectLens/actions/workflows/deploy-pages.yml/badge.svg?branch=main&event=push)](https://github.com/MatthewPaver/ProjectLens/actions/workflows/deploy-pages.yml)
diff --git a/docs/change-assurance.html b/docs/change-assurance.html
index 7389f53..2ebebbe 100644
--- a/docs/change-assurance.html
+++ b/docs/change-assurance.html
@@ -253,7 +253,7 @@ <h3>Similar cases from public records</h3>
   </main>
   </div>
 
-  <footer class="site-footer">Built by Matthew Paver · <a href="https://matthewpaver.github.io/store/apps/projectlens/">product notes</a> · <a href="https://github.com/MatthewPaver/ProjectLens#results">Technical evidence</a> · <a href="https://www.linkedin.com/in/matthew-paver-534262166/">LinkedIn</a> · <a href="https://matthewpaver.github.io/">matthewpaver.github.io</a></footer>
+  <footer class="site-footer">Built by Matthew Paver · <a href="https://matthewpaver.github.io/work/projectlens/">Case study</a> · <a href="https://github.com/MatthewPaver/ProjectLens#results">Technical evidence</a> · <a href="https://www.linkedin.com/in/matthew-paver-534262166/">LinkedIn</a> · <a href="https://matthewpaver.github.io/">matthewpaver.github.io</a></footer>
 
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   <script src="change-assurance.js"></script>