This book provides a thorough introduction to the physics of molecules and clusters in intense laser fields. It presents both theoretical and experimental aspects of the subject, and covers new research in the area of clusters in intense laser fields. The book discusses femto second pulse production and diagnostics, and covers diatomic and polyatomic molecules, as well as coherent control. This book will be of interest to graduate students and researchers in atomic, molecular and optical physics. It will also be suitable as a reference text for advanced physics courses.