Efficient communication architectures are vital for handling larger scale first response scenarios, and existing??mechanisms have several shortcomings due to the heterogeneity of??first response groups. In this paper, we consider using??peer-to-peer-based communication architectures for first response??scenarios.??We evaluated different network overlays in environments??found in first response -like scenarios.??A first response P2P??system needs to address both, reliability in high churn situations??in network infrastructure mode as well as reasonable usability in??wireless ad-hoc networks. Our evaluation shows that a superpeer??architecture based on peer capabilities has superior performance??when compared with purely unstructured or DHT-based overlays.