Micro-structured reactors were applied for processing of fuels such as propane to produce purified hydrogen for fuel cells. Mostly home-made wash-coated noble metal catalysts were introduced into micro-channels and applied for propane steam reforming (Rh/Pt/CeO2 on gamma-Al2O3), partial oxidation of propane (commercial Rh-catalyst), total oxidation of propane, water-gas shift (Pt/CeO2 on gamma-Al2O3) and the selective oxidation of carbon monoxide (Rh/Pt on gamma-Al2O3). Micro-structured reactor concepts for both catalyst testing and integrated heat-exchanger/reactors are presented. The latter allow for combining exothermal and endothermal reactions or combustion and evaporation in a single device. The size of the devices under investigation ranges from 100 W to 5 kW electrical output of the fuel cell, which is supplied with the hydrogen produced. Finally, a exemplary concept example of a complete fuel processor based micro-technology is discussed.