Integrated performance assessments of proposed repositories for HLW involve multidisciplinary studies which include identification of possible paths of future evolution of the repository system (scenario analysis) and quantification of the consequences of each scenario using deterministic or probabilistic modelling approaches. The results of such studies are commonly presented as estimates of consequence (e.g. dose to a representative individual) against time which extends into the distant future. Individual components of the model chains used can be tested to some extent, but how can the integrated assessment be evaluated to give additional confidence in the overall results? In order to address this issue, the Kristallin-l performance assessmentI has been compared with other HLW/spent fuel performance assessments. This technical comparison forms the basis of this paper which summarises the results from a more extensive comparison of a number of HLW/spent fuel disposal concepts, safety assessment methodologies and models2. It is part of a wider study which attempted to put the results of the Kristallin-I performance assessment into perspective by use of both this technical comparison with other performance assessments and by consideration of other information (e.g. natural analogue studies, environmental radiation data and risk assessments for radiological and non-radiological hazards) which allows the reasonableness of the results and significance of the predicted doses to be illustrated. Due to limitations of space, this aspect of the study has not been included here and the reader is referred to the “Kristallin-I: Results in Perspective” report2 for more details.