The uncooperative or noncompliant patient presents a substantial problem during treatment with removable orthopedic/orthodontic appliances. Frequently, the uncooperative patient is labeled as having a poor or defiant attitude toward orthodontic treatment. In contrast to this attitude model of patient noncompliance, this article presents an analysis of uncooperative behavior in terms of behavior-environment relationships. The authors bring together backgrounds of expertise in both clinical psychology and orthodontics. The behavioral model presented is applied to clinical orthodontic patients undergoing treatment with removable functional appliances. Preliminary research findings suggest that the behavioral model described is a successful system for the introduction of a removable device to be worn by the patient. The techniques described also are useful for the previously uncooperative patient undergoing remedial treatment. Another major benefit of using this strategy is found in the response of the children's parents. The approach reduces the potential for and frequency of parent-child conflicts over dental health. Currently, a small sample of children are being treated by the behavioral method. Both parents and patients are involved. A specific schedule for wearing of a removable appliance is identified, along with parental observations and rewards based on patient compliance. Once the youngster is regularly meeting criteria, the program is altered to increase the desired response of appliance wear. The behavioral model has implications for various aspects of orthodontic care, including the use of such appliances as the Fränkel, Bionator, headgear, intraoral elastics, and proper lip posture. On the basis of this functional analysis of behavior, implications for treatment and prevention of noncompliance in orthodontic patients are discussed.