diff --git a/README.md b/README.md
index e92cbcf..c0aa030 100644
--- a/README.md
+++ b/README.md
@@ -41,8 +41,14 @@ behind it.
 * **Windows**: [samplebrain_0.18_win.zip](https://static.thentrythis.org/samplebrain/samplebrain_0.18_win.zip)
 * **Mac**: [samplebrain_0.18_macintel.zip](https://static.thentrythis.org/samplebrain/samplebrain_0.18_macintel.zip)
 
-Contribution of a universal or apple silicon binary gratefully received (see building instructions below)
+Note: As this software is not on the apple store, to run this binary
+you need to tell your mac it's ok: Go to System Preferences > Security
+& Privacy > General. At the bottom of the window, select "Allow apps
+to be downloaded from Anywhere".
 
+Contribution of a universal or apple silicon binary gratefully
+received (see building instructions below)
+    
 **Linux install (Ubuntu)**
     
     $ sudo add-apt-repository ppa:thentrythis/samplebrain