Metallic microstructure devices have been manufactured and tested for applications in technical applications in thermal and chemical process engineering and in the laboratory. Manufacturing has been performed by micromachining of metal foils and diffusion bonding of a laminated foil stack, followed by welding of the microstructured core into a housing. Crossflow- and counterflow micro heat exchangers with microchannel or microcolumn structures have been developed for throughputs up to 7 t water / h with a heat transmission power up to 200 kW. Overall heat transfer coefficients up to 54,000 W/m2K have been determined with water as test fluid. Electrically driven microstructured heaters have been developed for fast and precise heating of sensitive liquids or gases. The heater has been used as evaporator as well. Static micromixers have been developed for fast and complete mixing of reactands. They can be utilized with parallel reactions, for example, to decrease the yield of undesired by-products. For heterogeneously catalyzed reactions, several methods have been developed to coat fluid passages of already manufactured microstructure devices with thin catalytic layers.