Lasers are relatively recent additions to the analytical scientist's arsenal. Because of this, many analysts-whether their concern is research or some range of applications-are in need of a tutorial introduction not only to the principles of lasers, their optics, and radiation, but also to their already diverse and burgeoning applications. The artic1es presented in this volume, carefully enhanced and edited from lectures prepared for the ACS Division of Analytical Chemistry 1979 Summer Symposium, are designed to provide just such a broad introduction to the subject. Thus, in addition to several excellent chapters on laser fundamentals, there are many practically oriented artic1es dealing with laser analytical methodology, inc1uding techniques based on the absorption oflaser radiation, on laser-induced fluorescence, and on some of the uses of lasers in chemical instru­ mentation. The first of these sections is pivotal and reflects in part our philosophy in organizing this collection. The authors of the initial chapters were invited not only because of their expertise in the field of lasers and analytical chemistry, but also because their didactic approach to writing and their c1arity of presentation were well known to us. It is our hope that individual readers with little knowledge of lasers will gain from these introductory chapters sufficient information to render the later, more detailed artic1es both useful and meaningful.