Agency is a fashionable concept, particularly among historians of poverty, welfare and charity in Britain in the long eighteenth century, and yet the concept is seldom scrutinized. This article troubles agency, subjecting it to the critical examination that it has largely eluded thus far. The first section outlines the manifold, and occasionally contradictory, ways in which historians characterize human agency. The second examines agency through the lens of charity in early nineteenth-century London (c.1800-c.1837), dissecting how the poor exercised agency in their interactions with charitable organizations and illustrating how philanthropists represented and sought to define the limits of plebeian agency. Case studies from individual charities test the boundaries of agency, proposing new ways of approaching the concept. The article concludes by reflecting on the usefulness of agency as a tool for historical analysis.