IN MAY 1976, Congress passed the Medical Device Amendments to the Federal Food, Drug, and Cosmetic Act. These amendments provide the Food and Drug Administration with substantial new authority in the regulation of new and existing medical devices. The term "medical device" includes all of the items readily identified as devices as well as in vitro diagnostic devices used in the clinical laboratory and some products previously regulated by the FDA's Bureau of Drugs, such as soft contact lenses and intrauterine devices, or by the Bureau of Biologics, such as some arterial grafts. The Medical Device Amendments included provisions designed to avoid the overregulation of certain devices. For instance, all medical devices are classified into one of three regulatory classes so that the amount of regulation for a device is proportional to the product's potential hazards. Class I devices are subject only to the general controls applicable to all devices,