This final report describes a project begun in 1962 which was designed to analyze the effect of home and maternal influence on the cognitive development of urban preschool children evaluated when they were four years old. The research group consisted of 163 mother-child pairs from three socioeconomic status levels: middle class, skilled working class, and unskilled working class. Subjects were selected from both father-present and father-absent families. The text of the report establishes empirical baselines and offers concepts and constructs related to family resources and maternal life styles, maternal control strategies and cognitive processes, mother-child interaction, cognitive behavior of mother and child, mother's language and the child's cognitive behavior. A summary chapter highlights project results. Extensive appendixes supplement the text by providing detailed analysis of testing techniques, interview procedures and statistical data. References are included. A follow-up report of academic performance and cognitive attainment during the children's first two years of school is available as PS 003 335. (WY)