diff --git a/docs/UserGuide.md b/docs/UserGuide.md
index d8baf467f73..e43fa22f84f 100644
--- a/docs/UserGuide.md
+++ b/docs/UserGuide.md
@@ -338,7 +338,8 @@ slightly easier.
 Format: `auto_pair`
 
 * The volunteer and elderly in each pair generated will 
-always have **matching regions** and **compatible availabilities**.
+always have **compatible regions and availabilities**.
+   * We consider a volunteer/elderly with no specified region to be compatible with _any_ region. Similarly, a volunteer/elderly with no availabilities specified will be considered to be available at _any_ time. 
 * In the event that no pairs can be formed satisfying the above constraints 
 (either because there are no unpaired volunteers or elderly, or all the unpaired volunteers 
 and elderly have incompatible regions or availabilities)