diff --git a/client/README.md b/client/README.md
index 6fcd1c92..d76316b4 100644
--- a/client/README.md
+++ b/client/README.md
@@ -36,8 +36,7 @@ Should this all go well you should be left with the file `looking-glass-client`
 ### Removing Wayland or X11 support
 
 Wayland and/or X11 support can be disabled with the compile options
-`ENABLE_WAYLAND` and `ENABLE_X11`, if both are specified only `SDL2` will remain
-and the client will fallback to using it.
+`ENABLE_WAYLAND=NO` and `ENABLE_X11=NO`. It is an error to disable both backends.
 
     cmake ../ -DENABLE_WAYLAND=OFF