describe the architectural challenges that have to be tackled to enable context aware services and applications in PNs and propose components for an efficient context management framework. In this paper we put special focus on the use of context information from and within the communication stack. We also address security and privacy issues that arise, if context information is to be shared between users in different PNs I. INTRODUCTION Personal Networks are a new network paradigm introduced in [1]. This type of network encompasses a user's personal area network (in our notation, the Private-PAN or P-PAN), but also his/her personal devices in remote locations like his/her office or his/her home. Figure 1 shows the conceptual structure of a Personal Network with the user's Private PAN as its core. An interconnecting structure connects the P-PAN with the user's personal devices and nodes at his/her home cluster, office cluster or whatever is currently interesting for the user to interact with. What is specific about this concept is that it provides the user with an easy and secure way of interacting with nodes, services and applications which have a personal relation to the user. This concept has been under development and research in the MAGNET Project, and is extended in the MAGNET Beyond project to also incorporate cooperative/federated networks of this type, e.g. if a user wishes to share services, resources or other information in a work relation or with his/her family. The Personal Network accompanies and supports the user wherever he/she goes. As the network is private, there is great potential in personalizing not just single applications, services or devices, but the whole computing environment to the user's needs. As the focus of the mobile user may be on real world tasks, proactive computer support becomes important. This proactive behaviour pertains to automatically adapting the