The subject of sintering (sometimes termed coarsening) has received considerable attention since the late 1960s, and a review [1] appeared in this journal in 1975. Significant progress has been made since then, in particular, with regard to the mechanisms and kinetics of sintering and measurement techniques. With these advances it is now possible to utilize the understanding gained for the design of reactors undergoing catalyst sintering. In fact, a few attempts have already been made.