Cruzan v. Director, Missouri Department of Health, the first "right to do die" case to be decided by the United States Supreme Court, constitutionalizes the principle of patient self-determination. The case encourages competent patients to reflect thoughtfully about the possibility that one day they may be incapacitated just as Nancy Beth Cruzan was and to prepare for that possibility by completing an advance directive. Furthermore, the recently enacted Patient Self-Determination Act requires hospitals to ask adult patients upon admission whether they have advance directives. However, a number of practical concerns arise for physicians about operationalizing these patient self-determination principles within their states and their scopes of practice. Will physicians be prosecuted for "assisting suicides" if they withdraw feeding tubes or forgo other life-sustaining treatments? Will physicians be liable in medical malpractice for "undertreatment" or "overtreatment" in such cases? Will physicians be asked to violate their own moral codes in treating patients? Will others intrude into the traditional physician-patient relationship and decision-making process? Will physicians be caught in the middle of troublesome family, staff, and institutional disputes? How will physicians learn of patients' advance directives? Will physicians be asked to continue care in futile cases? Will Cruzan's self-determination doctrine be improperly extended? Successful implementation of patient self-determination principles will require consideration and discussion of these practical physician concerns.