Protection of the public in a nuclear power plant emergency requires decision-makers to balance the time requirements from two chains of events: the events associated with a radiological release and the events involved with the response to that release. The management of these events is distributed among personnel at the nuclear plant, in the local community, and in state and federal agencies. All of these parties must coordinate their response to the emergency to assure that timely and effective protective response can be made by the risk area population. This article describes the process by which protective action recommendations (PARs) are developed in nuclear power plant emergency exercises and provides recommendations from research on emergency response in other types of natural and technological hazards.