How are religious educational institutions built? In histories of evangelical institution-building in the Victorian Indian colonial period (1858-1901), this question has mostly been addressed from the perspective of the religious ends that Christian missionaries sought to achieve and the ideological obstacles they encountered. This may be called the 'values' approach. Missionary Calculus sets this aside and examines, instead, the most routine transactions of missionaries in building an evangelical institution, the Sunday school. Missionaries daily struggled with and acted upon certain questions: How shall we acquire land and money to set up such schools? What methods shall we employ to attract students? What curriculum, books, and classroom materials shall we use? How shall we tune our hymns? Shall we employ non-Christians to teach in Christian Sunday schools? The makers of colonial Sunday schools focused obsessively on the means, the material and symbolic resources, with which they felt they could achieve certain immediate objectives. Such a transactional or 'instrumental' approach resulted in stated religious 'values' being insidiously compromised. Using insights from classical Weberian sociology, and through a close scrutiny of missionary means, this book shows how the success or failure of meeting evangelical ends may be assessed. With extensive archival research, chiefly on American missionaries in colonial India, this work examines the formation of Sunday schools at the point of transnational, intercultural contact. Readers interested in religion, education, and colonial history should find the matter, method, outcomes, and narration of Missionary Calculus new and thought-provoking.