The rapid progress in fabricating and utilizing microelectromechanical (MEMS) systems during the last decade is not matched by corresponding understanding of the unconventional fluid flow involved in the operation and manufacture of these small devices. Providing such understanding is crucial to designing, optimizing, fabricating and operating improved MEMS devices. Microfluid Mechanics: Principles and Modeling is a rigorous reference that begins with the fundamental principles governing microfluid mechanics and progresses to more complex mathematical models, which will allow research engineers to better measure and predict reactions of gaseous and liquids in microenvironments.Dr. William W. Liou received his Ph.D. degree from Penn State University in 1990. His doctoral research focuses on the theoretical modeling and computational simulations of turbulent fluid flows. He has worked as a Research Associate at the Institute for Computational Method in Propulsion at NASA Glenn Research Center for six years. His research activities at NASA involve studying the laminar and turbulent flow physics for propulsion. Since 1997, Dr. Liou has been working as an Assistant and an Associate Professor at Western Michigan University.Dr. Fang is a research fellow of Mechanical and Aeronautical Engineering at Western Michigan University. He received his M.S. degree from the University of Science and Technology of China, P. R. China, in 1998, and Ph.D. degree in mechanical engineering from the Western Michigan University in 2003. Since 1998, he started his research work in microfluid dynamics, which include theoretical and computational modeling by using both molecular- andcontinuum-methods.