This book provides a comprehensive description of microsensors for mechanical quantities (flow, pressure, force, inertia) fabricated by silicon micromachining. Since the design of such sensors requires interdisciplinary teamwork, the presentation is made accessible to engineers trained in electrical and mechanical engineering, physics and chemistry. The reader is guided through the micromachining fabrication process. A chapter on microsensor packaging completes the discussion of technological problems. The description of the basic physics required for sensor design includes the mechanics of deformation and the piezoresistive transduction to electrical signals. There is also a comprehensive discussion of resonant sensors, the hydrodynamics and heat transfer relevant for flow sensors, and, finally, electronic interfacing and readout circuitry. Numerous up-to-date case studies are presented, together with the working, fabrication and design of the sensors.