BACKGROUND: Most patients do not participate in advance care planning with physicians. OBJECTIVE: To examine patients' preferences for involving their physicians and families in advance care planning. DESIGN: Face-to-face interviews with randomly selected patients. SETTING: Community-based dialysis units in one rural and one urban region. PARTICIPANTS: 400 hemodialysis patients. MEASUREMENTS: Questions about whom patients involve in advance care planning, whom patients would like to include in this planning, and patients' reactions to state legislation on surrogate decision makers in end-of-life care. RESULTS: Patients more frequently discussed preferences for end-of-life care with family members than with physicians (50% compared with 6%; P < 0.001). More patients wanted to include family members in future discussions of advance care planning than wanted to include physicians (91% compared with 36%; P < 0.001). Patients were most comfortable with legislation that granted their family end-of-life decision-making authority in the event of their own incapacity (P < 0.001). CONCLUSION: Most patients want to include their families more than their physicians in advance care planning.