Membrane microreactors (MMRs) combine the advantages of membrane separation and microreactors such as high area/volume ratio, enhanced mass and/or heat transfer, improved catalytic efficiency without equilibrium limitation, good operational safety and design flexibility. This article presents a short review of recent developments in MMRs and in particular highlights their applications in catalytic processing. The structure and fabrication of MMRs, the incorporation of catalysts with membranes, the flow characteristics as well as their applications in a variety of catalytic processes are presented. The prospects and challenges of MMRs in catalytic processing are also presented and discussed. (c) 2013 Society of Chemical Industry