Hikikomori, which literally means “withdrawal,” is considered an increasingly prevalent form of social isolation in Japanese society. This issue has been attracting worldwide attention for two decades. Based on interviews with people who have experienced it, Teppei Sekimizu explores what the hikikomori experience is like from a sociological perspective. He also examines the characteristics of four decades of hikikomori discourse by governments, professionals, and mass media; the difficulties faced by parents with hikikomori children; and the social policy which has relegated most provision of welfare for citizens to the private sector. Through these examinations, the author illustrates how the exclusive labor market and familial social policies create masses of family-dependent and isolated individuals in contemporary Japan. A Sociology of Hikikomori leads the reader to a deeper understanding of the manifold hikikomori phenomenon and Japanese society itself.