Background: Patients in different countries have different attitudes toward self‐determination and medical information. Little is known how much respect Japanese patients feel should be given for their wishes about medical care and for medical information, and what choices they would make in the face of disagreement. Methods: Ambulatory patients in six clinics of internal medicine at a university hospital were surveyed using a self‐administered questionnaire. Results: A total of 307 patients participated in our survey. Of the respondents, 47% would accept (...) recommendations made by physicians, even if such recommendations were against their wishes; 25% would try to persuade their physician to change their recommendations; and 14% would leave their physician to find a new one. Seventy‐six percent of the respondents thought that physicians should routinely ask patients if they would want to know about a diagnosis of cancer, while 5% disagreed; 59% responded that physicians should inform them of the actual diagnosis, even against the request of their family not to do so, while 24% would want their physician to abide by their family's request and 14% could not decide. One‐third of the respondents who initially said they would want to know the truth would yield to the desires of the family in a case of disagreement. Interpretations: In the face of disagreement regarding medical care and disclosure, Japanese patients tend to respond in a diverse and unpredictable manner. Medical professionals should thus be prudent and ask their patients explicitly what they want regarding medical care and information. (shrink)