In response to the need for national-level, representative data on early childhood development before the start of formal schooling, the Measuring Early Learning Quality & Outcomes (MELQO) project was founded by three United Nations organizations and one non-governmental organization, UNESCO, UNICEF, the World Bank, and the Brookings Institution. In partnership with RTI International and Project Investigator Maria Dzula, this study examines the development and learning of 684 Tanzanian children starting school, averaging 7 years of age. A primary goal was to evaluate the psychometric properties of a globally-informed measure of school readiness. Using multiple measures including newly-developed direct assessment, and teacher and parent reports of child development, we hypothesized that children's development and learning would demonstrate expected constructs of academic and social/emotional skills and associations with family and child characteristics. Children's direct assessment scores factored into five domains measuring pre-mathematics, pre-literacy, executive functioning, fine motor skills, and socioemotional knowledge. Teachers' reports of children's social/emotional abilities factored into three domains measuring children's social competence, attention/self-regulatory abilities, and problem behaviors. Structural analyses indicated that children's attentional/self-regulatory abilities were associated with their direct assessment scores. Future research should examine these constructs in other countries, with additional methodologies to examine cultural fit and relevance.