LSAC is following the lives of two cohorts of approximately 5,000 children: an infant cohort (0 to 1 years old in Wave 1) and a child cohort (4 to 5 years old in Wave 1). This paper aims to explore how LSAC infants and 4 to 5 year-old children are doing, and to identify factors associated with variations in their functioning. It is based on Wave 1 data, and hence cross-sectional and exploratory in nature. This precludes drawing any implications about causal connections or pathways linking correlates and child outcomes. However, a broad range of factors are examined, ranging from sociodemographic characteristics of families to children's care and educational experiences. A multivariable approach to analysis is adopted, so that unique associations between child outcomes and these factors can be identified. Given the large and representative nature of the two LSAC cohorts, these data provide initial indications about a number of issues of policy relevance, although stronger tests of these must await later waves of LSAC data.