The different steps for manufacturing a microchannel reactor for the PROX reaction are discussed. Transient Liquid Phase bonding (TLP) using a Ni-B-Si amorphous melt spun is used for joining micromilled Al-alloyed ferritic stainless steel plates followed by recrystallization at 1200 degrees C for 5 h. A CuOx-CeO2 catalyst synthesized by the coprecipitation method was washcoated on the microchannel block resulting in a homogenous 20-30 mu m thick layer. The catalytic activity for CO-PROX reaction is similar in both the powder catalyst and the microchannel coated reactor but the selectivity is higher in the microchannel reactor. (C) 2010 Elsevier B.V. All rights reserved.