Book excerpt: The realizations of physical systems whose quantum states can be directly manipulated have been pursued for experiments on fundamental problems in quantum mechanics and implementations of quantum information devices. Micro-fabricated superconducting systems and electronic spins are among the most promising candidates. This book contains the newest and most advanced research reports on such materials, called “Mesoscopic Superconductivity” and “Spintronics”. The former includes superconductor-semiconductor hybrid systems, very small Josephson junctions, and micron-size SQUIDs. The latter includes the control of spin transports in semiconductor heterostructures, nano-scale quantum dots, and spin injections. Superconductor-ferromagnetic metal hybrid structures are covered by both of the topics.The proceedings have been selected for coverage in:• Index to Scientific & Technical Proceedings (ISTP CDROM version / ISI Proceedings)