This paper presents the �situation manager� rule language. The situation manager is a tool that includes both a language and an efficient run-time execution mechanism, aimed at reducing the complexity of active applications. It follows the observation that in many cases, there is a gap between current tools that enable to react to a single event (following the ECA: Event-Condition-Action paradigm), and the reality, in which a single event may not require any reaction, but the reaction should be given to patterns over the event history.

Abstract: Events are at the core of reactive applications, which have become popular in many domains.