diff --git a/tools/osx/INSTALL.readme.rtf b/tools/osx/INSTALL.readme.rtf
index 9a4183a0d..7d4aa060e 100644
--- a/tools/osx/INSTALL.readme.rtf
+++ b/tools/osx/INSTALL.readme.rtf
@@ -1,7 +1,9 @@
 To install the RawTherapee application:
 
 1. Open the RawTherapee .dmg Disk Image included alongside this document.
-2. To install RT, drag icon onto /Applications (it will not start if in another location).
+2. Drag the RawTherapee icon onto /Applications.
+
+Note: For security reasons, RawTherapee MUST be installed in /Applications. RawTherapee will refuse to start if installed elsewhere.
 
 To run the RawTherapee application: