This paper introduces complexity theory as a new conceptual approach to research in American Indian studies and, specifically, to gaming in Indian Country. Casinos may look like a good thing for Indian reservations. They can support economic development, tribal web pages, and the revitalization of tribal languages, arts, and community organizations. Less discussed, however, is the fact that a casino can also spawn major and irreversible changes in tribal communities. It can change the physical boundaries of a reservation through the acquisition of land and alter the membership of a tribe by redefining tribal roles for the purposes of distributing gaming receipts. An initial look at tribal responses to the 1988 Indian Gaming Regulatory Act (IGRA) through the prism of complexity theory suggests that Indian gaming holds within it the potential to both strengthen and weaken American Indian tribes and tribal sovereignty. THE INDIAN GAMING REGULATORY ACT The earliest stages in the development of profit-making Indian tribal gaming in the United States began in the 1970s when tribes in Florida, Connecticut, Wisconsin, and California first opened low-stakes bingo halls on their reservations and then gradually expanded their gaming enterprises. When the tribes began to offer higher stakes, stay open longer, and use paid workers rather than volunteers, they frequently came into conflict with adjacent state and local governments. When state officials charged the Indians with violating the law, tribal leaders responded that they were exercising their sovereignty and that state laws did not apply to their reservations.