IF THE READER FELT THAT the last chapter gave short shrift to an important subject, he may be outraged by the treatment presented here. The reason for such abbreviated coverage is that both absorption and emission spectroscopic techniques have an extensive and current literature authored by individuals far more knowledgeable and experienced in these areas. Our purpose with these chapters is to introduce these techniques and to illustrate how chemistry plays a role in their use. The reader is referred to the Bibliography and to the references that accompany these chapters for necessary details of both theory and application.