This document discusses the principle of autonomy in medical ethics. It begins by defining autonomy as self-rule or self-determination without undue external influence. The document then discusses how autonomy relates to informed consent and respecting patients' medical decisions. It also addresses challenges in applying autonomy, such as at the end of life or with patients who have impaired decision-making capacity. The document emphasizes that respecting patient autonomy involves providing full information, upholding confidentiality, and not overriding patients' preferences against their will.