Patients with cancer who are approaching the end of their lives, as well as the patients’ families and professional caregivers, often confront difficult decisions regarding the initiation, continuation, withholding, or withdrawal of various forms of medical care. Those clinical choices must be made and implemented within the prevailing legal environment. The legal environment in the United States surrounding and shaping medical decision making and care for dying cancer patients is explored in this chapter. Specific topics addressed include distinguishing living patients from dead bodies, informed consent and refusal, informational confidentiality in medical care, advance health care planning, medical decision making in the absence of advance planning, standards of care and medical malpractice liability, limits on the rights of patients and families, and postmortem rights and responsibilities.