diff --git a/config/application.rb b/config/application.rb
index 7b804402..1b492a3a 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -131,7 +131,13 @@ module Greenlight
     config.primary_color_darken_default = "#316cbe"
 
     # Default registration method if the user does not specify one
-    config.registration_method_default = config.registration_methods[:open]
+    config.registration_method_default = if ENV["DEFAULT_REGISTRATION"] == "invite"
+      config.registration_methods[:invite]
+    elsif ENV["DEFAULT_REGISTRATION"] == "approval"
+      config.registration_methods[:approval]
+    else
+      config.registration_methods[:open]
+    end
 
     # Default limit on number of rooms users can create
     config.number_of_rooms_default = 15
diff --git a/config/environments/test.rb b/config/environments/test.rb
index 42285acc..3936b7d4 100644
--- a/config/environments/test.rb
+++ b/config/environments/test.rb
@@ -55,4 +55,6 @@ Rails.application.configure do
   config.bigbluebutton_secret = config.bigbluebutton_secret_default
 
   config.loadbalanced_configuration = false
+
+  config.registration_method_default = config.registration_methods[:open]
 end
diff --git a/sample.env b/sample.env
index 9073a77d..f50bf80e 100644
--- a/sample.env
+++ b/sample.env
@@ -202,3 +202,11 @@ MAINTENANCE_MODE=false
 # DB_NAME=greenlight_production
 # DB_USERNAME=postgres
 # DB_PASSWORD=password
+
+# Specify the default registration to be used by Greenlight until an administrator sets the
+# registration method
+# Allowed values are:
+#   open - For open registration
+#   invite - For invite only registration
+#   approval - For approve/decline registration
+DEFAULT_REGISTRATION=open