John Illgen is a pioneer in the establishment of Modeling and Simulation in the Defense System Acquisition Process. Mr. Illgen has developed and applied models and simulations to the defense, civil and commercial communities. He is responsible for injecting simulation technologies across NGIS and, recently assisting across all sectors, developing and applying Modeling and Simulation by fostering DoD, Industry, Academic Best Simulation Practices and Technologies. At NGIS Mr. Illgen has led the development of a Modeling and Simulation Community of Practice to collaborate, facilitate, and coordinate M&S development and applications throughout NGIS key programs. He has also managed the development of online processes to maintain a library of models, simulations, M&S points of contact, and other resources to further foster the use and rapid application of M&S. John has a national and international reputation for his Modeling and Simulation experience and leadership in a broad spectrum of technical domains that include Network Enabled Systems, Communications, Architectures, Information Systems, Threat Evaluations, Command and Control, Sensors, and Weapons Systems.