The aim of this paper is to review building use and safety literature in relation to the concept of "vulnerability" or "vulnerable population groups". By definition "building use and safety" implies a relationship between people and the built environment in which "vulnerability" (susceptibility to accident and/or injury) is defined in terms of People (P), Actions (A), Environment (E). In this respect one or a combination of these components, will make a major contribution to an accident or disaster. An accident or disaster is often a consequence of a mismatch between people and features of a physical setting. Elderly people and children are usually considered as "vulnerable population groups" without reference to the built environment. To illustrate the fact that vulnerability should be considered in terms of the interrelationship between people and settings, reference is made to people who are "disabled" or "handicapped" and the issue of access to and egress from public buildings in the event of a fire. In this context, there has been the recognition not only that some people are vulnerable, but that their vulnerability is increased by exposure to risks posed by and in certain architectural settings. Recent examples of major crowd disasters in Britain are cited as instances where the people present were vulnerable population groups by virtue of poor safety management, inappropriate communications and design of the settings. Attention needs to be directed to the relative influence of (P) X (A) X (E) if appropriate safety principles are to be established. In this respect accident, disaster and injury prevention requires an interdisciplinary focus on psychological and social perceptions, political and economic impact of safety initiatives, medical policy and environmental design.