** Enhancing Donor Agency to Improve Charitable Giving: Strategies and Heterogeneity ------------------------------------------------------------------------ ** This research investigates whether charities can enhance fundraising effectiveness by increasing donors’ sense of agency. This article introduces two strategies to do so: allowing donors to target a specific charitable project via choice options (targeting-via-options) and allowing donors to target a specific charitable project via suggested donation amounts (targeting-via-options). A large-scale field experiment involving more than 40,000 prospective donors manipulates the ability to control the allocation of the charity’s resources and finds that enhancing donor agency boosts fundraising revenue by 42%. A causal forest analysis indicates significant donor heterogeneity with a subset of donors being three times more responsive to the opportunity to target their gift than the average donor. Inactive donors, clumpy donors (who exhibit uneven donation patterns) and donors who concentrate their gifts during the popular giving periods are less responsive to the interventions, while frequent, generous, and long-tenured donors are more responsive to them. Three experiments offer stronger internal validity regarding the manipulations and process evidence that agency and not emotion is responsible for the increased donation effects. An optimization analysis provides implications for how charities can leverage these insights to manage their fundraising campaigns to greater success. This repository contains supplemental materials including R codes, and data.