Reflecting recent advancements in colloidal nanocrystals and quantum-confined nanostructures, this second edition focuses on the semiconductor nanocrystals known as nanocrystal quantum dots. Gathering contributions from leading researchers, this edition includes new chapters on carrier multiplication (generation of multiexcitons by single photons), doping of semiconductor nanocrystals, and applications of nanocrystals in biology. The book also covers synthesis and assembly, spectroscopy of inter- and intraband optical transitions, single-nanocrystal optical and tunneling spectroscopy, transport properties, and nanocrystal applications in photovoltaics, light emitting technologies, lasing, bioimaging, and biosensing.