Temporomandibular dysfunction (TMD) pain, like many chronic pain problems, appears to be multiply determined. Patients with TMD pain of at least 6 months duration (N = 30) were administered questionnaires measuring dispositional coping styles and appraisals to explore the dynamic interactions of the pain and coping process. Patients were then issued handheld computers that prompted them to record their momentary pain and coping processes 4 times per day for 7 days. Hierarchical linear regression models using both the dispositional and momentary predictors indicated that momentary pain was a function both of dispositional tendency to catastrophize and of momentary measures of catastrophization, self-efficacy, and mood states. Results were seen as supporting a situational model of intervention for chronic TMD pain. Copyright 2004 American Psychological Association