diff --git a/README.md b/README.md
index 67d52a4cec..d3c8c5e44c 100644
--- a/README.md
+++ b/README.md
@@ -52,6 +52,8 @@ implementation 'com.google.android.exoplayer:exoplayer-dash:2.X.X'
 implementation 'com.google.android.exoplayer:exoplayer-ui:2.X.X'
 ```
 
+When depending on individual modules they must all be the same version.
+
 The available library modules are listed below. Adding a dependency to the full
 ExoPlayer library is equivalent to adding dependencies on all of the library
 modules individually.
diff --git a/docs/hello-world.md b/docs/hello-world.md
index 2ef28ed3bb..80dd002825 100644
--- a/docs/hello-world.md
+++ b/docs/hello-world.md
@@ -50,6 +50,8 @@ implementation 'com.google.android.exoplayer:exoplayer-ui:2.X.X'
 ~~~
 {: .language-gradle}
 
+When depending on individual modules they must all be the same version.
+
 The available library modules are listed below. Adding a dependency to the full
 ExoPlayer library is equivalent to adding dependencies on all of the library
 modules individually.