This report is concerned with the general problem of the effectiveness of simulator training and reflects information developed during the conduct of aircraft simulator training research projects sponsored by the Air Force, Army, Navy, and Cost Guard. Problems are identified related to simulator design, testing and use that impact 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.