Computer models have definite limitations regarding the representation of biological systems, but they do have useful applications in reducing the number of animals used to study physiological systems, especially for educational purposes. This guide lists computer models that simulate living systems and can be used to demonstrate physiological, anatomical, pharmacological, and medical concepts. The 48 programs are listed alphabetically and by subject; and an annotated description is given of each, including author, source, price, system requirements, and audience. (SLD)