Black holes, once considered to be of purely theoretical interest, play an important role in observational astronomy and a range of astrophysical phenomena. This volume is based on a meeting held at the Space Telescope Science Institute, which explored the many aspects of black hole astrophysics. Written by world experts in areas of stellar-mass, intermediate-mass and supermassive black holes, these review papers provide an up-to-date overview of developments in this field. Topics discussed range from black hole entropy and the fate of information to supermassive black holes at the centers of galaxies, and from the possibility of producing black holes in collider experiments to the measurements of black hole spins. This is an invaluable resource for researchers currently working in the field, and for graduate students interested in this active and growing area of research.