The increasing emphasis and importance of mesoscopic systems for tomorrow's high-tech electronics industry as well as a growing research interest in the subject has given rise to the need for a modern introductory text at the graduate level. This book aims to provide the necessary theory and tools to carry out research into the various aspects of the subject. It starts with a chapter on the theory of quantum transport giving a survey of the basic theory used in transport phenomena including scattering, linear response theory, weak localization, conductance fluctuations and the Landauer-Büttiker formalism. Various aspects of chaos in quantum systems as well as dissipative quantum systems are discussed. Other topics of importance such as single electron tunneling, driven bistable systems, quantized transport and electron liquids are also covered in detail. Graduate students as well as newcomers to this exciting and expanding field will find this work useful to adopt the necessary theory and overview required to go deeper into the original literature and to carry out research.