This report draws together the full findings of the process and cost evaluation of the two-year-olds in schools demonstration project. This was undertaken by the Research Centre of the National Children's Bureau (NCB), in partnership with the NCB Early Childhood Unit (ECU) and Frontier Economics (FE) from October 2013 until September 2014. This final report provides data from the final phase of the evaluation, alongside discussion of the lessons learnt from the evaluation overall and recommendations for sustaining and developing provision in schools for two-year-olds in the future. It is the third in a suite of documents, the first being a report detailing the baseline survey findings published in April 2014 and the second, a report of the eight case study schools which is published alongside this final report. (author abstract)