To advance knowledge and understanding about the dynamic use of childcare subsidies, this study uses administrative data from the child-care subsidy systems in five states (Illinois, Maryland, Massachusetts, Oregon, and Texas) to address the following questions about subsidy use and cross-state variation: (a) What are the characteristics of children and families who receive subsidies? (b) What assistance do these children and families receive? (c) How long do spells of subsidy receipt last? (d) How likely is it that children who end a spell of subsidy receipt subsequently begin another? and (e) How stable are children's care arrangements while they are in the subsidy system? (author abstract)