diff --git a/config/initializers/locale.rb b/config/initializers/locale.rb
new file mode 100644
index 000000000..3f99b5d9d
--- /dev/null
+++ b/config/initializers/locale.rb
@@ -0,0 +1,9 @@
+# i18n's old behavior was to not validate locales when
+# certain things were done with it. This behavior is now
+# deprecated, but is still the default. When i18n defaults
+# to the deprecated behavior, it prints a warning message.
+# Our options are to either explicitly choose the deprecated
+# behavior or switch to the new behavior, both of which
+# suppress the warning message. There doesn't seem to be any
+# reason not to switch to the new behavior, so we do that here.
+I18n.config.enforce_available_locales = true