IN THIS ISSUE: Mechanical Analysis and Design in Orthopedics /2 (Mechanical engineers working with physicians and veterinarians are making advances in such areas as the design of prostheses and orthopedic surgery. Donald L. Bartel, assistant professor of mechanical engineering, discusses his cooperative research program in biomechanics.) ... You Can Make an Artificial Kidney Out of a Cow's Hide /10 (A joint medical and engineering research project at Cornell is developing a natural material, collagen, for such applications as artificial kidney membranes, corneal grafts, and burn dressings. James F. Stevenson, assistant professor of chemical engineering, describes various aspects of the research.) ... The Development of an Isotopic Cardiac Pacer /16 (A Cornell mechanical engineering graduate was recently granted a patent for a longlived heart pacemaker with a radioactive power source. David L. Purdy, president of Coratomic, Inc., discusses the design and testing of the device in contract work for the Atomic Energy Commission.) ... How Drugs Work in the Body: A New Problem for Chemical Engineers /23 (Pharmacokinetics, the mathematical description of drug distribution in the body, is one of the areas of bioengineering research that are opening up to engineers. Kenneth B. Bischoff, director of Cornell's School of Chemical Engineering, discusses his research, including work on an anti-cancer drug, conducted in collaboration with the National Institutes of Health.) ... Register /28 ... Faculty Publications /33