This paper describes the Child Care and Development Fund (CCDF), the principal source of federal funding for child care subsidies for low income families and the principal source of federal funding for initiatives to improve the quality of child care in the states. Each state qualifies to receive an amount of federal funds under the CCDF each year and can receive additional federal funds by spending state dollars for child care subsidies and quality initiatives. Federal law established requirements that states must meet to receive CCDF funds, but states have very broad discretion in many of the basic design features of their low income subsidy programs and quality initiatives. It is estimated that about 1.5 million children receive CCDF-funded child care subsidies each month. To be eligible, a child must be under 13 years of age (or older if physically or mentally incapable of self-care). The child must reside with a family in which income does not exceed 85% of the state's median income for a family of the same size. To be eligible, a child must also reside with a parent(s) or legal guardian(s) who are working or attending job training; or a child must receive, or need to receive, protective services and resides with a parent(s) or guardian(s) who are not working or receiving job training. Other requirements are also specified. (SLD)