Alma Economics worked with the Independent Review of Children’s Social Care (the Review) to investigate the outcomes of children who need a social worker and related costs, as well as to estimate the costs and benefits of proposed recommendations to reform children’s social care. This research project comprised two phases. Phase 1 documented the lifetime cost to individuals, the state and society of adverse outcomes of children with a social worker. Phase 2 estimated the impact on public finances and produced an outline Cost-Benefit Analysis of the Review’s recommendations.This technical note is part of Phase 2. It provides more information on the modelling approach and it accompanies the model outputs.Estimates of the impact on public finances capture costs and savings to the public sector. The outline CBA takes a wider approach and reflects costs and benefits to society, following HM Treasury Green Book guidance. The frameworks used for estimating each type of cost are detailed below.Each recommendation is approached on a stand-alone basis – in other words, estimates do not directly take into account the interaction between different recommendations.