Changing patterns of maternal employment, coupled with stronger work requirements for welfare recipients, are increasing the demand for child care. For many families, the cost of child care creates a financial burden; for mothers with low incomes and those who are former welfare recipients, these costs may be an insurmountable barrier to employment or economic self-sufficiency. Despite increased public spending in this area, the receipt of any child care subsidy appears to be a relatively rare and uncertain event. In this study, we use data from a sample of low-income single mothers (current and recent welfare recipients in California) to estimate the probability of their receiving child care subsidies and the effect of this probability on labor market activity.