Approximately 90% of cardiac events are attributable to a small number of modifiable behavioral risk factors that, if changed, can greatly decrease morbidity and mortality. However, few at-risk individuals make recommended behavioral changes, including those who receive formal interventions designed to facilitate healthy behavior. Given evidence for the potential of specific psychological factors inherent in acceptance-based behavior therapy (ABBT; that is, intolerance of discomfort, mindfulness, and values clarity) to impact health behavior change, the authors evaluated the feasibility and initial effectiveness of an ABBT pilot program designed to increase adherence to behavioral recommendations among cardiac patients. Participants (N = 16) were enrolled in four, 90-min group sessions focused on developing mindfulness and distress tolerance skills, and strengthening commitment to health-related behavior change. Participants reported high treatment satisfaction and comprehension and made positive changes in diet and physical activity. This was the first evaluation of an ABBT program aimed at increasing heart-healthy behaviors among cardiac patients.