Abstract. Current Web applications embed sophisticated user interfaces and business logic. The original interaction paradigm of the Web with static content pages that are browsed by hyperlinks is, therefore, not valid anymore. We advocate a paradigm shift for browsers and Web applications, considering new kinds of events, side effects, and asynchronous interactions. Pages are replaced by States, and Back/Forward navigation along the browsing history is replaced by a full-fledged interactive application paradigm, featuring Undo/Redo capabilities, with support for exception management policies and transactional properties. This new paradigm offers a safer and more precise interaction model protecting the user from unexpected behaviours.