This document is the technical overview of the SAFIR 2 report that synthesises all of the technical and scientific knowledge available at the end of the second phase (1990–2000) of the ONDRAF/NIRAS programme of methodological research and development on the final disposal of category B and C waste in a poorly-indurated clay formation. The SAFIR 2 report will be handed over by ONDRAF/NIRAS to its supervisory Minister at the beginning of 2002, after publication approval by its Board of Directors.