Whether to inform patients that they have Alzheimer's disease can be a vexing issue. Two approaches to medical ethics may be used to address this issue: one takes a strong rights-oriented position; the other takes a best-outcome position. The interests that patients have in knowing relate to both schools of thought. The authors surveyed 224 adult patients who were waiting to see their physicians. The findings showed that over 90 percent of patients want to be told of the diagnosis. Reasons for wanting to be told included making plans for care, obtaining a second opinion, and settling family matters. No demographic markers could be used to predict who would not be told. Even though several patients indicated that reading a case description made them feel suicidal, reactions to not being told are generally negative. Following either ethical approach leads to the conclusion that patients ought to be told. Subjects' interests in whom else should be told were also recorded, raising questions of confidentiality.