How quality of center-based child care relates to early cognitive and language development was examined longitudinally from 6 to 36 months of age in a sample of 89 African American children. Both structural and process measures of quality of child care were collected through observation of the infant classroom. Results indicated that higher quality child care was related to higher measures of cognitive development (Bayley Scales of Infant Development), language development (Sequenced Inventory of Communication Development), and communication skills (Communication and Symbolic Behavior Scales) across time, even after adjusting for selected child and family characteristics. In addition, classrooms that met professional recommendations regarding child:adult ratios tended to have children with better language skills. Classrooms that met recommendations regarding teacher education tended to have girls with better cognitive and receptive language skills. These findings, in conjunction with the growing child-care literature, provide further evidence that researchers and policymakers should strive to improve the quality of child care to enhance early development of such vulnerable children.