The field of optical and laser remote sensing has grown rapidly in recent years. This dynamic growth has been stimulated not only by technological advances in lasers, detectors, and optical system design, but also by the potential application of remote sensing systems to a wide variety of atmo­ spheric measurements. Optical and laser remote sensing can allow single­ ended measurement capability not offered by conventional point-detection techniques. While many past measurements have been associated with labo­ ratory research. practical systems have recently been developed which are capable of remotely detecting. measuring. and tracking a wide range of molecular and atomic species in the atmosphere with concentrations of parts per billion and at ranges over 100 km. This book is a compilation of papers which represent an overview of the present state of development of optical and laser remote sensing tech­ nology. The subjects covered include both passive and active remote sen­ sing techniques in the UV, visible, and IR spectral regions. related laser and detector technology, and atmospheric propagation and system analysis considerations. While the papers do not constitute an exhaustive treat­ ment of the excellent research being conducted in this field, they are representative of the wide diversity of present efforts. It is hoped that the reader will gain a general understanding of the current research in optical and laser remote sensing as well as an overview of current systems development.