Today, fluorescence spectroscopy is an important tool of investigation in many areas. In analytical sciences, its advantage is extremely high sensitivity and selectivity - even single molecules can be detected - and it achieves a high spatial resolution and time resolution in combination with microscopic techniques or laser techniques, respectively. In material sciences, this is used to study structure and dynamics of surfaces. Particularly in the areas of biochemistry and molecular genetics, fluorescence spectroscopy has become a dominating technique. Together with the latest imaging techniques, fluorescence spectroscopy allows a real-time observation of the dynamics of intact biological systems with an unprecedented resolution. This book offers a comprehensive introduction to and survey of fluorescence spectroscopy. It is written for newcomers and active researchers alike who are learning to apply fluorescence methods in the areas of chemistry, physical chemistry, polymers, materials, colloids, biochemistry, biology, medical and pharmaceutical research.