diff --git a/README.md b/README.md
index 468425cee43..63e9a2bf2ab 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,8 @@ Release binaries can be found on [on github](http://github.com/TASVideos/BizHawk
 
 [Developer build](https://ci.appveyor.com/project/zeromus/bizhawk-udexo/build/artifacts) of the most recent commit
 
+Never mix different versions of BizHawk. Keep each version in its own folder.
+
 ## Supported Systems
 
  * Nintendo Entertainment System / Famicom / Famicom Disk System (NES/FDS)