At a time when Government budget cuts are in vogue and increased military readiness is the goal, knowledge of cost estimating and cost/training effectiveness models is essential for decision-makers and training analysts. As with many aspects of our economy, costs associated with training continue to climb. Understanding and correctly using cost estimating and cost/training effectiveness models can help in the area of controlling the costs associated with training. This paper will present a number of the more common cost and training effectiveness models, describe the use of the models and develop a glossary of terms. The material presented here is by no means exhaustive. The intent is to introduce the reader to some of the techniques available and to provide a starting point for learning more about the subject. By being aware of and correctly using these and other types of cost estimating and cost/training effectiveness models, decision-makers will be able to increase the return on the investments made in military training systems. By using these techniques, it will become possible to achieve the goal of receiving better training for less cost.