Two ways.
i. You can put it in ApplicationController and add the filters in the controller
class ApplicationController < ActionController::Base def filter_method end end class FirstController < ApplicationController before_filter :filter_method end class SecondController < ApplicationController before_filter :filter_method end But the problem here is that this method will be added to all the controllers since all of them extend from application controller
ii. Create a parent controller and define it there
class ParentController < ApplicationController def filter_method end end class FirstController < ParentController before_filter :filter_method end class SecondController < ParentController before_filter :filter_method end I have named it as parent controller but you can come up with a name that fits your situation properly.
You can also define the filter method in a module and include it in the controllers where you need the filter