Previous research has focused on cross-cultural comparisons of illnesses, such as depression and senile dementia, though few have studied the actual processes by which these illness categories become separated from their roots and adopted in a different locale; in anthropological terms, their "indigenization." Through anthropological fieldwork conducted from June to September of 2003, this paper explores how dansei konenki, or male menopause, has found a niche in contemporary Japan, as well as the defining features of the country that may explain this phenomenon. Based on this research, I argue that the indigenization of dansei konenki embodies a particular socio- historical moment in Japan-namely, that of the long-running economic decline in recent years.