The most important concern in the design, construction and operation of nuclear powerplants is safety. Nuclear power is one of the major contributors to the nation's supply of electricity; therefore, it is important to assure its safe use. Each different type of powerplant has special design features and systems to protect health and safety. One safety concern that is unique to producing electricity at nuclear powerplants is the potential for accidents involving radioactivity. The safety features of a nuclear powerplant are designed to provide maximum safety and to minimize the chance of accidental emission of radiation. This publication reports on the following: (1) safety by design which includes natural safeguards, physical containment barriers, and engineered safety systems; (2) safety through planning of siting, licensing, emergency response, and insurance; (3) Three Mile Island; and (4) safety first. (RT)