The Effective Provision of Pre-School Education (EPPE) project is the first major European longitudinal study of a national sample of children's development between the ages of 3 and 7 years. EPPE collected a wide range of information on 3,000 children, their parents, home environments and the pre-school settings they attended. Settings (141) were drawn from a range of types of providers (local authority day nursery, integrated centres, playgroups, private day nurseries, nursery schools and nursery classes). A sample of 'home' children (who had no or minimal pre-school experience) were recruited to the study at entry to school for comparison with the pre-school group. In addition to investigating the effects of pre- school provision, EPPE explores the characteristics of effective practice (and the pedagogy which underpin them) through twelve intensive case studies of settings with positive child outcomes. The study has demonstrated the positive effects of high quality provision on children's intellectual and social/behavioural developmental measured at the start of primary school. The study has had impact at national level (through research evidence to the Sure Start unit and the Treasury for the Spending Review), at local level (through work with LEAs seeking advice on reconfiguring their services) and at practitioner level (through keynote addresses, conferences, seminars and workshops). The paper presented at this conference will report on the effects of pre-school up to the end of Key Stage 1 (at the age of 7 years) to establish whether the pre-school effects apparent at entry to school remain or are 'washed out' as the effects of primary school become more apparent. The paper will also describe the continuation of the EPPE study; the Effective Pre-School and Primary Education 3-11 (EPPE 3-11, 2003 - 2008) which continues to build on the extensive data collected in the original EPPE study, following the children up to the age of 11 at the end of Key Stage 2. EPPE 3-11 is interested in the continual effects of pre-school education, the characteristics of effective primary schooling, the learning trajectories of resilient and vulnerable children and the contribution of out of school learning. The new project will adopt an innovative design that will explore the identification of effective primary schools using quantitative data derived from analyses of matched data sets across Key Stages. This quantitative data will inform focus school observations which will explore the practices and process at classroom level which may influence children's cognitive and social/behavioural development. The study combines statistical analyses, observational and interview data.