The idea is simple; an MCV controller can decide to redirect a client to a specific URL, to a specific controller method. A typical example would be that an anonymous user hits a page that required to be logged; the controller will then redirect the user to a login page. To do this, the controller uses HTTP 302 ('moved temporarily') to invite the client to make a new request to a different URL, to a different controller. That second request implies a new (and thus different) request-response cycle. And that's the 'raison-d'être' of this newscope, i.e. to allow maintaining some state between the 2 request-response cycles of a redirect. Note that this new scope is for the MVC API only. That new scope is sometime referred as the 'Flash scope'. You can see how both redirect andworks here