Abstract
Agency is inescapably plural in both concept and measurement. In Sen's account of agency, (i) agency is exercised with respect to goals the person values; (ii) agency includes effective power as well as direct control; (iii) agency may advance wellbeing or may address other-regarding goals; (iv) to identify agency also entails an assessment of the value of the agent's goals; and (v) the agent's responsibility for a state of affairs should be incorporated into his or her evaluation of it. This chapter refracts the literature on agency measurement through the first four of these characteristics, showing how particular survey-based measures of individual agency elucidate or obscure each distinction. It also observes that existing measures used in development tend to focus on control but not effective freedom, on goals the agent has reason to value rather than goals she values, and on own rather than other-regarding agency. The literature on measurement also raises a number of very relevant issues for the conceptual approach.