Magnetic and superconducting materials pervade every avenue of the technological world from microelectronics and mass-data storage to medicine and heavy engineering. This Concise Encyclopedia draws together for the first time in a single volume the remarkable advances seen in recent years in the discovery of new materials and improvements of existing materials, in the elucidation of a new and deeper understanding of their phenomenology and in the expansion and diversification of their application in technology. Magnetic and superconducting materials have much in common; they have both experienced, over the last decade, a revolution that has revitalised and galvanised their respective fields. In each case the impetus has come from the discovery of new materials; this, in turn, has stimulated a re-evaluation of a wide range of basic mechanisms and phenomena. The encyclopedia is based on newly commissioned articles and articles revised from the acclaimed Encyclopedia of Materials and Engineering. Details of all important materials systems and their properties are included and key areas such as thin films are covered. The volume contains 110 articles, alphabetically organised and written by over 120 acknowledged experts within the field of magnetic and superconducting materials. Each article discusses in turn one aspect of the subject and includes, where appropriate, photographs, line drawings and tables to aid the understanding of the topic under discussion. Cross-references guide readers to articles covering subjects of related interest and the bibliography at the end of each article indicates the most important recent literature.