This mixed-methods multiyear (2010–14) study, the Illinois–New York Child Care Research Partnership Study: Phase 1, analyzed the experiences of a new cohort of child care subsidy clients residing in four sites in Illinois and New York. The study used longitudinal state administrative data from child care payment records in combination with newly collected telephone survey and qualitative interview data from subsidy clients to identify patterns of program use and to examine factors that predict exits from the subsidy program and from subsidized providers. This research report discusses findings from the administrative data analysis and telephone survey.