The Japanese medical profession has come under increasingly intense scrutiny from the media and the public. Calls for recasting the traditional paternalistic doctor-patient relationship have become sufficiently pervasive that the medical profession itself has accepted the need to incorporate "infomudo konsento" (the English term is commonly used, for lack of a satisfactory phrase in Japanese) into medical practice. The medical establishment is attempting to accomplish this endeavor in a tamed and "Japanized" form which preserves professional autonomy. This paper attempts to illuminate the distinctive tenacity of Japanese medical paternalism. First, the paper presents a descriptive model of cultural paternalism characteristic of traditional Japanese medicine, taking as examples four specific practices: concealing from patients the diagnosis of cancer; withholding from patients information about drugs; requiring patients to sign waivers of rights; and refusing patients access to their own medical records. Second, the paper describes how the economic structure of Japanese health care reinforces these cultural proclivities toward paternalism. Third, the paper explores the paradox of the legal system's treatment of informed consent issues. The paper then addresses the sources of a gradual transformation in attitudes concerning informed consent. Emphasis is given to transformative forces peculiar to Japan: the controversy over brain death and organ transplantation, in which the rhetoric of informed consent has come to be used by all parties as a weapon of convenience and the enforcement (amidst publicity surrounding deaths from experimental drugs and international pressures for drug exports to meet accepted standards of biomedical ethics) of rules requiring informed consent in clinical trials of investigational drugs. The paper finally assesses the impact of the 1995 report of the prestigious Study Commission on Informed Consent.