Our knowledge of the photodegradation of polymers, chemical evolution, photosynthesis, visual perception and the biological effects of light depends heavily on our ability to elucidate the primary photochemical processes of macromolecules. This volume brings together for the first time from the fields of natural as well as synthetic polymers a group of reports dealing with macromolecular photochemistry. Since macromolecular photo­ chemistry is an expanding new field that crosses the boundaries between classical disciplines, the reader will encounter the employment of diverse scientific approaches and unfamiliar terminology. However, it has become increasingly apparent that researchers in these fields have much to learn from each other. Although this book is not intended to give a detailed survey of the photochemistry of macromolecules. it does represent the editor's perspective on the relationship between theory, kinetic studies and the synthesis aspects of photochemistry. The ideas expressed by the contributors offer a valuable com­ posite of theoretical and experimental approaches for those who are concerned with problems which have photochemical relevance, and show that investigators from different fields share many concepts and perhaps some common problems. This novel array of present knowledge should provide a basis for organizing and understanding photochemical information from chemistry, physics, biology and medicine. While of particular value to the research worker, the book also should be of interest to the graduate student about to embark on a problem in macromolecular photo­ chemistry.