Occupational science is a new scientific discipline that is defined as the systematic study of the human as an occupational being. A doctoral program in occupational science has been established at the University of Southern California, Los Angeles, With its emphasis on the provision of a multidimensional description of the substrates, form, function, meaning, and sociocultural and historical contexts of occupation, occupational science emphasizes the ability of humans throughout the life span to actively pursue and orchestrate occupations. In this paper, occupational science is described, defined, and distinguished from other social sciences. A general systems model is presented as a heuristic to explain occupation and organize knowledge in occupational science. The development of occupational science offers several key benefits to the profession of occupational therapy, including (a) fulfillment of the demand for doctoral-level faculty members in colleges and universities; (b) the generation of needed basic science research; and (c) the justification for and potential enhancement of practice.