Nonabandonment is one of a physician's central ethical obligations; it reflects a longitudinal commitment both to care about patients and to jointly seek solutions to problems with patients throughout their illnesses. The depth of this commitment may vary depending on the physician's and the patient's values and personalities, their shared experiences, and the patient's clinical circumstances. Traditional principled ethical analyses must balance the personal histories, values, motivations, and intentions of the participants with more general considerations. Such analyses often focus on a particular act, isolated in time, and yet the consequences of one decision immediately lead to a new set of choices. Nonabandonment places the physician's open-ended, long-term, caring commitment to joint problem solving at the core of medical ethics and clinical medicine. There is a world of difference between facing an uncertain future alone and facing it with a committed, caring, knowledgeable partner who will not shy away from difficult decisions when the path is unclear.