My paper entitled “Policy Fields, Data Systems and the Performance of Nonprofit Human Service Organizations has been published in a special issue of the journal Human Service Organizations: Management, Leadership, & Governance focusing on human service agencies and the question of impact. This research, a collaboration with Dr. Lehn Benjamin and Chris Bopp presents findings from case studies of the data systems in two nonprofit human service organizations—one in the HIV/AIDS field and the other in the homeless services field—and the larger data ecosystems in which these organizations and their data systems were situated. We examined how data entered the organization, were processed inside the organization, and then shared and/or reported outside the organization. These in-depth examinations of the data systems of two focal nonprofits were complemented by fieldwork carried out to understand the larger data ecosystems—including interviews with representatives from other service providers that were part of the focal organization’s referral network and organizations responsible for aggregating data at the community level, such as local government funders. By looking at the larger data ecosystem of each focal organization, we were able to see that these systems were more fully explained by the larger policy field in which these organizations worked. We describe three characteristics of the policy field that help explain our findings: the location of administrative authority, the funding tool, and assumptions about the policy problem. We conclude by discussing the implications of using policy fields as a lens for understanding nonprofit data systems as well as the limitations of our findings.