Yellowstone National Park and the surrounding areas are acclaimed for the quality and preservation of their natural environment. The social system enmeshed with that natural environment has received minimal theoretical consideration. The natural and human environments are interdependent, each largely dependent yet conceptually independent of the other. The national parks and adjacent wilderness exist by political fiat and are subject to future modification because of social and cultural factors. Conversely, the natural system presents considerable opportunities and limitations for human uses. A human ecological perspective is utilized to describe the relationships between the natural area and the social system, following Park and Burgess (1925) and Schnore (1958). Characteristics of the population, their technology, and social organization are summarized for five concentric zones emanating out from Yellowstone and Grand Teton National Parks. The processes of development and preservation in the region are described, particularly in peripheral areas lacking the legislated protection of the national parks.