The application of a value-impact methodology to a nuclear safety system design analysis has been investigated. The theoretical framework of multi-attribute decision theory and cost-benefit analysis is combined with reliability, availability, and probabilistic risk assessment techniques to analyze three design alternatives for the auxiliary feedwater system of a pressurized water reactor. Selected attributes pertaining to financial impact, investment risk, health risk, and licensability are used to rank the alternatives. External factors—such as the effect on the schedule of other plants, impact on property value, and emotional effects on population—that are potentially large were not considered. Standard reference tables were developed as a user’s guide for value-impact calculations.