This dissertation is a social history of the urban community of lay Buddhist elites, known as "householders," that vigorously pursued a mission of Buddhist activism in Shanghai during the first half of the twentieth century. The Shanghai householders were capitalists, doctors, lawyers, intellectuals and party members who chose to make a formal commitment to Buddhism and its goals of salvation yet retained their status as regular members of society with families and careers. They comprised the largest and most influential of the elite lay Buddhist communities that sprang up in cities across China during the Republican era. This study analyzes the social significance of the Shanghai householder community as it transitioned through a series of social and political upheavals from its emergence in the 1920s to its eventual demise amidst the transition to socialism in 1956. I argue that throughout these years Buddhist activism constituted an arena of civic culture in which urban elites were able to establish a durable source of moral authority and social legitimacy.