Patients with co-occurring health risk behaviors suffer greater morbidity, disability, and premature death. The Pro-Change Population Health Solution (PCPHS) is a suite of mobile tools designed to assist patients and primary care providers (PCPs) in applying evidence-based principles of health behavior change to reduce four cancer risk behaviors—cigarette smoking, risky drinking, noncompliance with national guidelines for physical activity, and overweight and obesity—and depression among at-risk patients. The intervention is based on the Transtheoretical Model of Behavior Change (TTM, the "stage model") and includes computer-tailored interventions and text messages for patients and a clinical dashboard for providers. The efficacy of the intervention will be assessed in a cluster-randomized trial involving 780 patients recruited from 12 federally qualified health centers randomly assigned to intervention or usual care.