diff --git a/README.md b/README.md
index 2388cbe..f92105f 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,9 @@ $ ninja -C build
 
 Cage comes with compile-time support for XWayland. To enable this,
 first make sure that your version of wlroots is compiled with this
-option. Then, add `-Dxwayland=true` to the `meson` command above.
+option. Then, add `-Dxwayland=true` to the `meson` command above. Note
+that you'll need to have the XWayland binary installed on your system
+for this to work.
 
 You can run Cage by running `./build/cage APPLICATION`. If you run it
 from within an existing X11 or Wayland session, it will open in a