This research report sets out a body of evidence which aims to form the basis for engagement within the public interest legal service sector, and between the sector and the donors which support it. The report examines the context within which public interest legal services are provided, and discusses what the available literature and the informants interviewed during the research (including legal practitioners, NGOs, social movements, donors, and judges) say about how to characterize the value and impact of work within the sector. The report goes on to propose a multidimensional approach to characterising the value of public interest legal services – one which focusses on issues and the way that they are framed, and which tries to account for both the direct and indirect material impact as well as the broader political and symbolic value of particular interventions. The report also address the ways in which people and organisations within the public interest legal services sector work together, and what donors should do, should not do, and can do better, to facilitate co-ordination and collaboration that is appropriate to existing needs and practices. Finally the report identifies the unacceptably high cost of legal services as a major obstacle to the public interest legal services sector’s capacity to facilitate access to justice. SERI conducted extensive research and wrote the final report, which was funded by the RAITH Foundation and the Ford Foundation.