The Young Lives survey is an innovative long-term project investigating the changing nature of childhood poverty in four developing countries. The purpose of the project is to improve understanding of the causes and consequences of childhood poverty and examine how policies affect children's well-being, in order to inform the development of future policy and to target child welfare interventions more effectively. The objectives of the study are to provide good quality long-term data about the lives of children living in poverty, trace linkages between key policy changes and child welfare, and inform and respond to the needs of policymakers, planners and other stakeholders. Research activities of the project include the collection of data on a set of child welfare outcomes and their determinants and the monitoring of changes in policy, in order to explore the links between the policy environment and outcomes for children. The study is being conducted in Ethiopia, India (in Andhra Pradesh), Peru and Vietnam. These countries were selected because they reflect a range of cultural, geographical and social contexts and experience differing issues facing the developing world; high debt burden, emergence from conflict, and vulnerability to environmental conditions such as drought and flood. The Young Lives study aims to track the lives of 12,000 children over a 15-year period. This is the time-frame set by the UN to assess progress towards the Millennium Development Goals. Round 1 of the study followed 2,000 children (aged between 6 and 18 months in 2002) and their households, from both urban and rural communities, in each of the four countries (8,000 children in total). Data were also collected on an older cohort of 1,000 children aged 7 to 8 years in each country, in order to provide a basis for comparison with the younger children when they reach that age. Round 2 of the study returned to the same children who were aged 1-year-old in Round 1 when they were aged approximately 5-years-old, and to the children aged 8-years-old in Round 1 when they were approximately 12-years-old. Round 3 of the study returned to the same children again when they were aged 7 to 8 years (the same as the older cohort in Round 1) and 14 to 15 years. It is envisaged that subsequent survey waves will take place in 2013 and 2016. Thus the younger children are being tracked from infancy to their mid-teens and the older children through into adulthood, when some will become parents themselves. Further information about the survey, including publications, can be downloaded from the Young Lives website. School Survey: A school survey was introduced into Young Lives in 2010, following the third round of the household survey, in order to capture detailed information about children’s experiences of schooling. It addressed two main research questions: • how do the relationships between poverty and child development manifest themselves and impact upon children's educational experiences and outcomes? • to what extent does children’s experience of school reinforce or compensate for disadvantage in terms of child development and poverty? The survey allows researchers to link longitudinal information on household and child characteristics from the household survey with data on the schools attended by the Young Lives children and children's achievements inside and outside the school. A wide range of stakeholders, including government representatives at national and sub-national levels, NGOs and donor organisations were involved in the design of the school survey, so the researchers could be sure that the ‘right questions’ were being asked to address major policy concerns. This consultation process means that policymakers already understand the context and potential of the Young Lives research and are interested to utilise the data and analysis to inform their policy decisions. The survey provides policy-relevant information on the relationship between child development (and its determinants) and children’s experience of school, including access, quality and progression. This combination of household, child and school-level data over time constitutes the comparative advantage of the Young Lives study. School Survey data are currently only available for India and Peru. The Peru data are available from the UK Data Archive under SN 7479. Further information is available from the Young Lives School Survey webpages.