<div> Chalcogenide glasses are promising materials for photonic applications due to their unique properties and functionalities. They are transparent from the visible to the near infrared region and can be molded into lenses or drawn into fibers. One of the most commercially successful applications has been lenses for infrared cameras. Chalcogenide glass fibers and optical components, such as waveguides, have been developed for use with lasers, for optical switching, chemical and temperature sensing and phase change memories. Contributors to part one cover preparation methods and properties of chalcogenide glasses. In part two they explore their photonic applications.<BR> <br> Part one outlines the preparation methods and properties of chalcogenide glasses, including the thermal properties, structure, and optical properties, before going on to discuss mean coordination and topological constraints in chalcogenide network glasses and the photo-induced phenomena in chalcogenide glasses. This section also covers the ionic conductivity and physical aging of chalcogenide glasses, deposition techniques for chalcogenide thin films, and transparent chalcogenide glass-ceramics. Part two explores the applications of chalcogenide glasses, such as rare-earth-doped chalcogenide glass for lasers and amplifiers, infrared sensing, microstructured optical fibres for infrared applications, and chalcogenide glass waveguide devices for all-optical signal processing. Chapters further discuss the control of light on the nanoscale with chalcogenide thin films, chalcogenide glass resists for lithography, and chalcogenide for phase change optical and electrical memories. The book concludes with an overview of chalcogenide glasses as electrolytes for batteries.</div>