Microreaction technology, with its unprecedented heat and mass transfer advantages as well as uniform residence time and flow pattern, is one of the few technologies with potential to develop efficient, environmentally benign, and compact processes. Novel fabrication and processing techniques, equipment, and operational methods are resulting in spectacular developments that go beyond “traditional” chemical engineering. These new developments promise improvements in process plants, and lead to the transformation of our concept of chemical plants into compact, safe, energy-efficient, and environmentally sustainable processes. Microsystems are now available in many devices for commercial applications including: micromixers and microreactors as alternative to batch production in pharmaceutical and fine chemical industry, lab-on-chip devices, microsensors, advanced rapid throughput chemical and catalyst screening tools (e.g. combi), distributed or portable power and chemical production, distributed heating and cooling, and even out of this world applications with NASA. A wide diversity of subjects are discussed in this book ranging from catalysis to fuel processing to combinatorial techniques to separations to novel reactors all of which are enabled by microtechnology principles. World renowned pioneers (Klavs Jensen, Volker Hessel, Jennifer Holmgren, and Galip Akay) provide accounts on both historical developments and the current state of the art as well as insights into future research and development in microreactor and process intensification. Research and developments are presented by industry, universities, U.S. National Laboratories, and other laboratories located in the United States and throughout the world. It is composed of peer-reviewed chapters from both contributing and invited authors. The review and original research topics include (1) introductory and general overviews, (2) microreactors- including catalysts for microreactors, fuel processors, milli-second contact time catalysis, gas to liquid technology, and biomass conversion; and (3) process intensification such as micro mixers, reactive membranes, and intensification of separation operations.