The Oklo Natural Analogue Project, Phase II was conducted by an international consortium of researchers under the sponsorship of the European Union. An important objective of the project was to examine the potential for extracting quantitative information from the Oklo natural reactors that could be used in performance assessment calculations for high level nuclear waste repositories. This paper discusses the uses and limitations of natural analogues with respect to performance assessment of repositories, the types of data needed in performance assessment calculations, the particular example of spent fuel dissolution rates, and the types of data available from Oklo studies that might contribute to understanding spent fuel behavior in a geologic setting. The main conclusions of this assessment are that important qualitative information has been obtained from studies at Oklo that gives us confidence that major processes of importance to the long-term behavior of a high level waste repository have not been overlooked in previous performance assessment calculations, but that the Oklo natural analogues are very unlikely to provide quantitative data to use as input to PA calculations.