This is the first in a series of three resources designed to help researchers interested in using administrative data. The other briefs in this series are entitled Determining the Feasibility of Using State Administrative Data and Considerations in Preparing to Analyze Administrative Data to Address Early Care and Education Related Research Questions. This first resource on building relationships with state partners is intended primarily for researchers who are new to the analysis of administrative data, although seasoned researchers may find it useful as well. State agency staff may also find the resource helpful in learning about the possible benefits of partnering with researchers. The resource was informed by conversations with Child Care Policy Research Partnership grantees, state agency staff, and researchers with experience analyzing state administrative data.