diff --git a/marketing-checklist.md b/marketing-checklist.md
index 55281e4..7fb1470 100644
--- a/marketing-checklist.md
+++ b/marketing-checklist.md
@@ -31,6 +31,7 @@ This section pairs nicely with the [Pre-Launch section of the Sales Checklist](h
   ##### Site monitoring tools
   - [ ] [Site Alerts](http://sitealerts.com/)
   - [ ] [Versionista](https://versionista.com/)
+  - [ ] [Page Delta](https://pagedelta.com/)
 
 - [ ] Subscribe to industry newsletters, magazines, trade journals etc.
 - [ ] Use [Google Trends](https://trends.google.com/trends/) to do initial demand and search volume research ([check out this article for specific tips](http://smallbusinessbc.ca/article/how-use-google-trends-perform-market-research/)).