The inherent freedom due to a lack of central authority in self-organized mobile ad hoc networks introduces challenges for security and trust management. Arguably, trust management is the most critical security issue in mobile ad hoc networks. If nodes do not have any prior knowledge of each other, the trust establishment becomes complicated. In these kinds of situations the nodes themselves should be responsible for their own security. We propose a model for security management in self-organizing mobile ad hoc networks that is based on the nodes? own responsibility of their security and node-level security monitoring.