In Japan, where a prominent gap exists in what is considered a patient’s best interest between the medical and patient sides, appropriate decision-making can be difficult to achieve. In Japanese clinical settings, decision-making is considered an act of choice-making from multiple potential options. With many ethical dilemmas still remaining, establishing an appropriate decision-making process is an urgent task in modern Japanese healthcare. This paper examines ethical issues related to shared decision-making (SDM) in clinical settings in modern Japan from the psychocultural-social (...) perspective and discusses the ideal decision-making process in present Japan. Specifically, we discuss how five psychocultural-social tendencies – “surmise (Sontaku),” “self-restraint (Jishuku),” “air (atmosphere or mood, Kuuki),” “peer pressure (or tuning pressure, Docho-Atsuryoku),” and “community (Seken)”—which have often been referred to as characteristics of present-day Japanese people, may affect the ideal practice of SDM in Japanese clinical settings. We conclude that health care professionals must be aware of the possible adverse effects of the above Japanese psychocultural-social tendencies on the implementation of SDM and attempt to promote autonomous decision-making, thereby allowing patients to make treatment choices that sufficiently reflect their individual and personal views of life, experiences, goals, preferences, and values. (shrink)