Concerned with the general problem of the effectiveness of simulator training, this report reflects information developed during the conduct of aircraft simulator training research projects sponsored by the Air Force, Army, Navy, and Coast Guard. Problems are identified related to simulator design, testing, and use, all of which impact upon simulator training effectiveness. These problems are (1) isolation of the simulator user from the design and development process, (2) inattention to behavioral and training models during that process, (3) ignoring training considerations during simulator testing, (4) inadequate feedback to simulator designers concerning simulator training effectiveness, (5) inattention to techniques of simulator training that differ from techniques of aircraft training, (6) inadequate training for simulator instructors, (7) use of rate of simulator utilization as an index of its training effectiveness, and (8) inadequacies of simulator training cost effectiveness data. (It was concluded in this report that to deal with these problems simulator training must be viewed as a part of a much larger training system and not as an independent element.) (Author/JH)