The authors use the ECLS-B, a nationally-representative study of children born in 2001 to report the child care arrangements and quality characteristics for 2-year olds in the United States and to estimate the effects of differing levels of child care quality on two-year old children's cognitive development. Their goal is to test whether high quality infant care can help close early achievement gaps between low-income children and their middle and high-income age-mates. (Contains 3 tables and 1 figure.)