Between June 2018 and November 2020, the National Foundation for Educational Research (NFER) conducted an evaluation of the Tailored Support Programme (TSP) on behalf of the Department for Education (DfE). The aim of the evaluation was to explore perceptions of the TSP and, in particular, gather data on: reasons for engagement; what was delivered; what worked well and less well and why; perceived impacts; sustainability; challenges in engaging with the programme; and what has been learnt for future recruitment and retention programmes. The evaluation included baseline surveys with senior leaders and teachers, as well as telephone interviews with a range of stakeholders at baseline and end-point. It is worth noting that end-point evaluation activities scheduled for April-July 2020 were impacted by COVID-19, and a lower number of interviews and case studies were completed than intended. The report primarily focuses on the findings from interviews and case studies with system leaders, senior leaders, early-career teachers (ECTs) and mentors. It also presents key findings from baseline surveys of senior leaders and teachers. [For "Evaluation of the Tailored Support Programme: Technical Appendix of Survey Responses," see ED612554.]