The book stresses the fundamental processes occurring in gas discharges and develops the analytical methods used to calculate important process rates. This background is then applied to detailed analyses of a variety of gas discharges with atomic, ionic and gas lasers being used as primary illustrations as well as important topics of study in their own right. However, the general processes and methods of analysis considered are applicable to any aspect of weakly ionized gas discharges. This book proceeds from the simplest models of a gas discharge through the most complex as the need for greater sophistication becomes apparent. Chapters one through six follow this sequence and complete the analytical framework for the study of gas discharges. Chapters seven through nine blend this framework with a thorough consideration of fundamental rate processes in order to establish the temporal and spatial behavior of charged, neutral and excited species in pulsed and D.C. discharges. Chapters ten through twelve then proceed to an in depth analysis of selected atomic, ionic and molecular gas lasers that are of significant current interest.