The purpose of this project is to evaluate the impact of home-based child care provider (HBCP) unionization on the cost, type, and availability of subsidized child care in Illinois. In 2005, Illinois became the first U.S. state to grant home-based child care providers the rights to form a union and bargain collectively with the state government. This policy inspired similar efforts across the country and represents a potentially important trend in child care policy. In other industries, labor unions have helped workers negotiate higher wages and develop a stronger voice in determining workplace practices. Among public-sector workers, unions have also been responsible for expanding the size of the unionized portion of the public-sector labor force. This project will use a recently developed quasi-experimental method to evaluate whether unionization had similar effects on child care in Illinois.