The increase of digital bandwidth and computing power of personal computers as well as the rise of the Web 2.0 came along with a new web programming paradigm: Rich Internet Applications. On the other hand, powerful server-side business rules engines appeared over the last years and let enterprises describe their business policies declaratively as business rules. This paper addresses the problem of how to combine the business rules approach with the new programming paradigm of Rich Internet Applications. We present a novel approach that reuses business rules for deriving declarative presentation and visualization logic. In this paper we introduce a rule-driven architecture capable of executing rules directly on the client by implementing the Rete algorithm. We propose to use declarative rules as platform independent language describing the application and presentation logic. By means of AJAX we exemplarily show how to use client-side executable rules for adapting the user interface of Rich Internet Applications. We call our approach ARRIA: Adaptive Reactive Rich Internet Applications. In order to show the usability of our approach we explain our approach based on an example taken from the financing sector.