Training engineering, a new model for computer-based training (CBT), has been devised and put into use by the Cognitive Engineering Design and Research Team (CEDAR) at Los Alamos National Laboratory. Training engineering is the application of scientific principles to the design, construction, and operation of efficient training systems. Such an approach is necessary because of the level of complexity CBT design and development has reached with the new advanced technologies. Instructional designers are under pressure to implement these new technologies more rapidly than has been required in the past, yet few models have emerged to aid designers in this process. Training engineering is such a model. It provides techniques for design and development that are derived from successful engineering techniques. This paper begins with a discussion of the engineering approach and then applies this approach to training. Examples from prototype CBT projects at Los Alamos are used throughout to illustrate the training engineering concept.