Effective medical treatment at the Point of Injury (POI), en-route to the treatment facilities, could enhance combat casualty care and decrease battlefield mortality. However, most combat casualty care systems are based on proprietary hardware and software, making it difficult to securely and transparently integrate wireless capabilities for monitoring, intervention, and communications between civilian and military networks. IAI and its collaborator, TrellisWare Technologies, Inc., are developing SWAC3, the Secure Wireless Architecture for Combat Casualty Care, that enables robust, secure, and efficient sharing of medical data among medical units, improving combat casualty care over complex and dynamic tactical networks. SWAC3 utilizes a tactical medical data cloud that can provide distributed data storage, processing, and presentation services with a web- and mobile-based user interface. The cloud receives and stores data collected from medical sensors, then processes and enriches the data, and finally transmits the processed metadata to casualty care units. Distributed data storage services will provide SWAC3 both high scalability and availability of the system. The users, equipped with mobile devices and computers, interact with the cloud through a visualization and retrieval application. A suite of security solutions will be provided for access control, key management, authentication, and data integrity for the cloud. Leveraging IAI's extensive experience with cloud computing, distributed system development, and cloud cluster infrastructure with realistic evaluation capabilities, the team has demonstrated the feasibility of SWAC3 cloud services and user interface, and will now refine the design to develop a fully functional prototype system.