Mobile Users (MUs) require flexible, reactive service delivery due to their regularly changing location and activities and the lack of a wired Internet connection. A mobile service delivery system should be able to detect relevant events that occur such as change of location, availability of new last-minute specials, sales opportunities and safety issues and then reactively take action in response to these events. This paper describes a framework for delivering such a system. Issues addressed include MU and service states and events, context, situations and situation-action rules, and syntactically and semantically compatible XML schemas for their specification. A framework is proposed that is based on distributed, co-operating software agents and mobile data technologies.