Although prisons provide on-site primary care, the corrections system relies on external hospitals to provide a variety of healthcare services. Compared to the general population, incarcerated patients experience higher rates of chronic medical conditions, mental illness, substance abuse, cancer, traumatic brain injury, assault, and communicable disease. Certain specialties of clinicians are likely to encounter patients who are incarcerated, which makes it important for clinicians to understand how medical decision-making may differ when the patient is a prisoner. The corrections system retains (...) custody of inmates and is responsible for their welfare, including facilitating necessary medical care. However, this does not permit corrections personnel or a warden to automatically assume the role of the patient's medical decision-maker. Except for narrow exceptions, prisoners do not lose their rights to medical decision-making. In some instances, corrections staff or the prison warden have improperly asserted authority to act as the patient's medical decision-maker, such as when the patient lacks decision-making capacity. This violates ethical principles of bodily integrity, respect, and fairness. This paper provides an overview of medical decision-making for incarcerated patients, how surrogate decision-maker hierarchies apply to incarcerated patients without decision-making capacity, and special considerations for this subset of patients. (shrink)