The book describes the nature of atomic and molecular spectra, with particular emphasis on luminescence, as well as the principles of laser operation. It acquaints latent print examiners with the basic physical principles underlying laser detection of latent prints, since questions about these principles may arise during court testimony. Then instrumentation and techniques of optical spectroscopy are detailed, with special attention to absorption, emission, and excitation spectral measurements. Next, the application of spectroscopic measurements to latent fingerprint detection is discussed. The description of instrumentation is restricted to a flexible and cost-effective modular spectroscopic system whose components can be rearranged for a variety of tasks. The text also discusses latent print detection by inherent fingerprint luminescence, describes a variety of latent print treatments which lead to laser-detected luminescence, and presents case applications. In addition, the use of optical spectroscopy in latent fingerprint detection by laser is described. Filters are explicitly treated, and potential uses of lasers and optical spectroscopy in forensic work are considered. Finally, the text briefly discusses operating and maintaining argon-ion lasers. Figures, color photographs, chapter references, additional readings, and an index are given. (Author abstract modified)