The recent development of microscale technologies makes it possible to design complex microsystems devoted to transport, dosing, mixing, analysis or even synthesis of fluids. Applications are numerous and exist in almost every industrial field, from biotechnology and healthcare to aeronautics and advanced materials manufacturing. Microfluidics is a relatively new research area, usually comprising work with microsystems and involving internal fluid flows with characteristic dimensions of the order of one micrometer (1 x 10 -6 m). This book provides engineers and researchers with a range of tools for modeling, experimenting on, and simulating these microflows, as a preliminary step in designing and optimizing fluidic microsystems. The various consequences of miniaturization on the hydrodynamics of gas, liquid or two-phase flows, as well as on associated heat transfer phenonema, are analyzed. The book is illustrated with examples that demonstrate the wide diversity of applications, and the breadth of novel uses of these fluidic microsystems.