Objective. To assess whether providing information on arthritis self-management through general practitioners (GPs) increases the quality of life in patients with osteoarthritis and whether additional case management provided by practice nurses shows better results. Methods. We conducted a pragmatic, cluster-randomized, controlled, 3-arm trial that included 1,021 patients from 75 primary care practices in Germany. GPs were randomized to intervention group I, group II, or a control group. GPs of both intervention groups participated in 2 peer group meetings. In intervention group II, additional case management was conducted via telephone by a practice nurse. The primary outcome was change in quality of life, assessed by the German version of the Arthritis Impact Measurement Scales Short Form (AIMS2-SF). Secondary outcomes were health service utilization, prescriptions, and physical activity. Data were controlled for depression using the Patient Health Questionnaire 9 as a potential confounder. Results. Of 1,125 administered questionnaires, 1,021 were analyzed. Compared with the control group, no significant changes occurred in intervention group I with respect to the primary outcome. Performed radiographs decreased significantly (P ؍ 0.050), whereas prescriptions of acetaminophen increased significantly (P < 0.001). In intervention group II, significant changes in the AIMS2-SF dimensions social (P < 0.001), symptom (P ؍ 0.048), and lower body (P ؍ 0.049) were identified. Radiographs (P ؍ 0.031) and orthopedic referrals (P ؍ 0.044) decreased whereas prescriptions of pain relievers increased significantly. Conclusion. Improving the quality of life in patients with arthritis using arthritis self-management seems challenging. Simply providing this information through GPs is not sufficient but combining it with case management seems to be a promising approach.