diff --git a/helper/resource/testing.go b/helper/resource/testing.go
index 4f46d2ba4..d8a2b253a 100644
--- a/helper/resource/testing.go
+++ b/helper/resource/testing.go
@@ -34,7 +34,13 @@ type TestCase struct {
 	// acceptance tests, such as verifying that keys are setup.
 	PreCheck func()
 
-	// Provider is the ResourceProvider that will be under test.
+	// Providers is the ResourceProvider that will be under test.
+	//
+	// Alternately, ProviderFactories can be specified for the providers
+	// that are valid. This takes priority over Providers.
+	//
+	// The end effect of each is the same: specifying the providers that
+	// are used within the tests.
 	Providers         map[string]terraform.ResourceProvider
 	ProviderFactories map[string]terraform.ResourceProviderFactory