This paper reviews and classifies publications dealing with catalytic membrane reactors in How-through mode. In contrast to other membrane reactor concepts, the membrane is operated in dead-end mode and no separation task is performed. As no permselectivity is required, catalytically active porous, Mostly ceramic, membranes are applied. The task of the membrane is to provide for intensive contact between reactants and catalyst; combined with a short contact time and a narrow residence time distribution. The applications are categorized in three groups: Complete Conversion Integral Reactors, Selective Integral Reactors and Selective Differential Reactors. (C) 2008 Elsevier B.V. All rights reserved.