This paper provides detail on two key components of the Houdini framework under development at Bell Labs, that enable context-aware and privacy-conscious user data sharing appropriate for mobile and/or ubiquitous computing. The framework includes an approach for integrating data from diverse sources, for gathering user preferences for what data to share and when to share it, and a policy management infrastructure in the network for enforcing those preferences. The current paper focuses on two components of this infrastructure that are essential for mobile and ubiquitous computing, namely the framework to support self-provisioning of preferences, and the performance of the underlying rules engine.