This report attempts to develop a theoretical framework for understanding firesetting behavior in terms of social learning theory. An advantage of the social learning approach is that it provides a unified functional approach to classification, theory, and therapeutic change, and that there is some continuity between an understanding of firesetting and an understanding of the determinants of behavior in general. Three major aspects of the interaction between a person's behavior and the social environment are considered. At the behavioral level, the individual's behavior acts upon and is acted upon by the environment, and aspects of the rearing environment which may lead to firesetting are considered. Vicarious processes determine how behavior is influenced by other sources of information, including modeling and instructional influences. Cognitive processes determine how a person selects, encodes, and evaluates incoming information about the social environment, and how behavioral sequences are determined in light of the person's expectations and abilities. These three components, which are considered basic processes in a person's successful adaptation to the environment, sometimes interact in ways which produce and maintain deviant behavior patterns, including firesetting. The implications of social learning theory for treating firesetting in children and adults are discussed in detail. While the importance of social learning processes in the development and maintenance of behavior has received wide empirical support, applications to firesetting behavior have largely been unexplored. Figures and about 135 references are provided. (Author abstract modified)