The paper introduces a formal archive for intercomparison of conventional regulatory dispersion models. It stems from an initial intercomparison, for the UK Environment Agency, of the USEPA's ISC and AERMOD models with the ADMS model, in common use in the UK. The objective is to compare the models directly with one another via standard test cases in order to reveal differences that may arise in regulatory modelling, rather than with field data as is used for model validation purposes. These latter data are too variable to provide accurate intercomparison between models. The archive contains all model input and output files, related reports and meteorological data so that any interested parties can continue intercomparison studies on this basis or with any other similar models. The archive is available, free, to interested parties by downloading it from the internet or on CD by request.