Contemporary behaviorism traces its roots to the philosophies of ancient Greece, the Renaissance, and the scientific revolution. It is not as much a product of early experimental psychology as it is a descendant of certain developments in the biological sciences carried out by Charles Darwin and others who studied the mind and certain continuities of behavior and biology existing among several species. Contemporary behaviorism attempts to explain human behavior by examining five integrated factors: (1) the person as a biological entity and as a contributor to behavioral interactions, (2) environment as a structural entity and as a contributor to behavioral interactions, (3) media of contact between person and environment such as light and sound waves, (4) the historical context of person and those environmental interactions giving rise to the evolution of current stimulus and response functions, and (5) the current biological and environmental setting that influences how interactions between the evolved person and the environment will occur at any particular time. It is noted that while the roots of contemporary behaviorism go back thousands of years, the application of this conceptual system to the problems of crime and delinquency is relatively recent. 229 references.