Considerable practical experience has been gained in applying non-testing approaches for regulatory purposes, most recently driven by the demands of the REACH legislation (EC, 2006). This ECETOC Task Force was convened to summarise guidance and tools available, to review their practical utility and to consider what technical recommendations and learnings could be shared more widely to refine and inform on the current use of read-across. A number of case studies were formulated and the generic insights of developing, evaluating, justifying and documenting read-across approaches were extracted as far as possible.