According to a cultural psychological perspective on self, many psychological tendencies are importantly constituted by multifaceted aspects of culture (such as ideas, dicourses, practices, and institutions), which in turn are rooted in the historically transmitted, and socially shared views of self as independent (predominant in North American and West European middleclass cultures) or as interdependent (predominant in Eastern cultures including Japan). Drawing on this theoretical framework, we first reviewed a vast body of studies on Japanese self, available in and out of Japan, across several social science disciplines, and identified several defining characteristics of the interdependence as it is instantiated in the contemporary Japanese society. Next, in order to illuminate some specific ways in which psychological tendencies are shaped by culture, we summarized our own Japan-US comparative research program on culturally divergent forms of self-realization and their consequences on mental and physical health. Directions for future research were discussed.