The Submarine Advanced Reactive Tactical Training System (SMARTTS) will be the "training subsystem" of the 21A Series Submarine Combat System Trainers. SMARTTS is the result of a series of research and development investigations directed by the U. S. Naval Training Equipment Center investigating the application of advanced training technology to submarine tactics training. SMARTTS is expected to greatly enhance the tactics training process by improving the quality and quantity of tactics training and by correcting current deficiencies of the tactics training system. The advanced training technology embodied under SMARTTS will present emerging concepts and capabilities that should be initially developed as an integral part of every simulator-based training system. The paper summarizes the SMARTTS program placing particular emphasis on the development of the SMARTTS characteristics as a result of a modified instructional systems development analysis. The SMARTTS characteristics, which are primarily implemented via software additions to the simulator programs, are applicable to virtually every simulator-based training system. SMARTTS will be a major addition to the Submarine Combat System Trainers; it represents a milestone in that it is a major subsystem, emphasizing advanced training technology as an integral part of the training device.