This volume is the proceedings of the 5th International Conference on Quantum Communication, Computing , and Measurement, held in Capri in July 2000, and covers all areas of quantum information science, which has developed dramatically recently. An excellent overview of the current topics in the field, it discusses quantum information theory, quantum measurement theory, decoherence, and entanglement theory as the theoretical aspect of quantum information science. Also included are quantum communication systems, quantum computing, quantum cryptography, new quantum effects and their experiments, generation and detection of nonclassical light, and teleportation as applications of quantum information science. In addition, the result of the third international quantum communication award is introduced.