This thesis explores the customary freshwater fishing rights of the New Zealand Maori through detailed examination of Maori evidence as to the nature and extent of these rights, and of Pakeha interpretations based upon both observation and upon Maori evidence. Most of the recorded evidence from Maori who exercised customary fishing rights in the nineteenth century was given in Pakeha institutions, notably the Native Land Court. The legal, political and intellectual context in which Maori gave their evidence is important for an understanding of Pakeha interpretations constructed from Maori evidence, and for the analysis of this evidence. In the first part of the thesis, modern reinterpretations of customary Maori rights (based on both traditional Maori knowledge and recent research) are examined for an understanding of Maori concepts of their freshwater fishing rights. The development of successive Pakeha interpretations of Maori customary rights from the beginnings of Pakeha settlement is then traced and contextualized. Particular attention is paid to the Native Land Court minutes, the most comprehensive source for Maori statements on fishing rights. The impact of the Court on the way Maori gave evidence and on Pakeha interpretations of Maori tenure and rights, the Court's legislative framework and key methodological issues are analysed. The second part of the thesis comprises four local case studies, which use Court evidence given by Maori to analyse in depth the nature and extent of freshwater fishing rights. Wairarapa Moana provides examples of both a large seasonal eel fishery, and a smaller-scale fishery in the fringing swamps. Lake Taupo is an example of a large lake fishery with a range of species, while the Whanganui River had a large and varied river fishery. The themes explored include the derivation oftitIe and rights, the scale of fishing rights, relationships between land and fisheries, and issues of property rights, management and control.