This presentation will discuss the decision process we followed to develop an ultrasound simulator. The development of an advanced technology medical device always requires tradeoffs and compromises between what is desired, and what can be realistically achieved. The medical applications of computer based education are increasingly important to the process of medical education. Product developers will be required to address these concerns. Some tradeoffs result from technical, scientific, and engineering factors; while others are the result of marketing, financial, or competitive constraints. All of these factors will influence the design and production of simulation tools. A manager, scientist, or engineer who is involved in development of this kind of innovative product may be helped by considering the impact of some of these decisions earlier in the process. Forewarned is fore-armed. The most basic design issue we faced was the conflict between the requirements we envisioned for the ultrasound simulator, and the limitations of realistic simulation. Our goal was to achieve a product which would be affordable to the academic institutions who would be using it. Simulation will be defined and presented with examples from our experience.