Postmodernism and postmodern social science theory represent a significant challenge to the foundational beliefs of professions such as social work. This thesis examines the origins of the specific issues involved through a broad historical review of relevant Western philosophy, sociological theory, and criminological theory. An attempt is made to demonstrate the progression of developments in Western philosophy and social science heory which have led to postmodernism by identifying the crucial metaphysical elements of this critical school of thought. The profession of social work is then examined in relation to these elements. The thesis concludes with an evaluation of the validity of postmodernism and the utility of employing this theoretical movement within the field of social work.