Active and engaged patients seek the understanding, knowledge, and skills to promote their own health. Efforts to promote such patient activation and engagement are ethically justified because they are consonant with the well-established principle of respect for persons and, as the evidence shows, because they are likely to produce better outcomes for patients. Yet patient activation and engagement can also go ethically awry if, for example, nonadherent patients are abandoned or are unduly disadvantaged by punitive policies and practices, or if the conditions for successful activation and engagement are missing. In this article we discuss the ethical issues and responsibilities that pertain to patients, clinicians, health care organizations, delivery systems, insurers, payers, and communities. For example, physicians or payers could hold patients blameworthy for not following recommendations, but we suggest that a better approach would be for providers and payers to empower patients to effectively share responsibility for defining goals and achieving them. An ethical approach to patient activation and engagement should place obligations not only on patients but also on clinicians, health care organizations and delivery systems, insurers, and communities.