The Tutor Trust is a Manchester-based charity that aims to provide affordable small group and one-to-one tuition, predominantly to disadvantaged pupils in schools in challenging communities. The tutors are university students and recent graduates, enabling tuition to be provided at a competitive rate on a not-for-profit basis. This three-year evaluation assessed the impact of the Tutor Trust on the English and mathematics GCSE results of 1,029 Year 11 pupils. Tuition took place in the academic years 2011-2012 to 2013-2014. Students received different numbers of hours of tuition, and some received tuition in multiple academic years between Year 9 and Year 11. The evaluation also explored schools' perceptions of the need for affordable tuition and their assessment of the quality of the service provided. Qualitative fieldwork took place in eight schools and was based on interviews with senior leaders, classroom teachers, tutors and pupils. The project was funded by the Education Endowment Foundation (EEF), Manchester City Council and payments from participating schools. A separate evaluation of the impact of the tuition on the English and mathematics attainment of Year 6 and Year 7 pupils is available on the EEF website. Key conclusions include: (1) Due to the limitations of the study design and the absence of a high-quality comparison group, this evaluation has not provided a secure estimate of the impact of the project on academic outcomes; (2) Participating pupils achieved slightly higher mathematics GCSE scores than pupils in the comparison group, and lower English GCSE scores than pupils in the comparison group. However, it is not possible to attribute either change to the tuition provided; (3) Schools involved in the qualitative interviews were positive about the tuition, keen to work with the Tutor Trust again, and largely confident that the tuition was beneficial for their pupils; (4) Teachers believed that there was a need for more affordable high-quality tuition, and that the Tutor Trust helped meet this need; and (5) It is recommended that the Tutor Trust continues to monitor tutor performance and identifies mechanisms to increase the consistency of tuition. Schools should be active participants in this process and classroom teachers need to be involved in the planning and management of tuition to ensure that in all cases tuition complements work in the classroom.