Abstract
Traditional informed consent often promotes passive acquiescence rather than active exercise of autonomy. A more natural biologically based model of autonomy is needed, a model that both recognizes the biological roots and therapeutic benefits of active confident choices among real alternatives, and offers substantive guidelines for promoting patient autonomy. A biological model of patient autonomy explains the value of information to patients, outlines the circumstances under which patients make effective choices, and suggests complementary roles for patients and professional caregivers.