In order to explore the domain of air-to-air combat with Soar, a uniied theory of cognition used to model human behavior, it was necessary to interface Soar to vehicles which use the Distributed Interactive Simulation (DIS) protocol. Rather than create what would be in essence a simulator of ghter aircraft, the ModSAF simulation system was chosen to simulate ghter aircraft and provide a DIS interface. To link Soar and ModSAF, we have developed the Soar/ModSAF Interface (SMI). The SMI provides a simulated cockpit for Soar pilots. To guide others in the development of interfaces for other intelligent systems, this paper describes the SMI along with associated design constraints. Implementation details concerning functionality, modularity, and eeciency are addressed. We also identify issues arising from integration diiculties.