diff --git a/auth_results.go b/auth_results.go
new file mode 100644
index 0000000..c8e7a55
--- /dev/null
+++ b/auth_results.go
@@ -0,0 +1,11 @@
+package gophercloud
+
+// AuthResults encapsulates the raw results from an authentication request. As OpenStack allows
+// extensions to influence the structure returned in ways that Gophercloud cannot predict at
+// compile-time, you should use type-safe accessors to work with the data represented by this type,
+// such as ServiceCatalog() and TokenID().
+type AuthResults interface {
+
+	// Retrieve the authentication token's value from the authentication response.
+	GetTokenID() (string, error)
+}