This Child Rights Impact Assessment considers the impact of tax, tax credit and welfare benefit changes and of changes to spending on public services implemented (or scheduled to be implemented) between May 2010 and April 2015. As a State Party to the United Nations Convention on the Rights of the Child (UNCRC), the UK is obliged under international law to use the maximum extent of its available resources to fulfil children’s right to an adequate standard of living, to social security, health, education and other economic and social rights. The purpose of the assessment is to identify the likely impact of budgetary decisions on the realisation of the rights of children in England, and to assess how far the UK Government has met its obligations to make the best interest of children a primary consideration in decisions – including budgetary decisions – affecting children. The assessment is based on analysis carried out for the Office of the Children’s Commissioner by a team from Landman Economics, using microsimulation models to assess the likely impact of tax-benefit and public expenditure changes on children living in different kinds of families. This is the first time such analysis has been undertaken and it provides a comprehensive breakdown of the impact some of the Government’s key policies have had, and will have, on families with children. Despite some progressive policies, families with children have lost more as a result of the economic policies modelled than those without children, and some of the most vulnerable groups have lost the most.