Book excerpt: Organic Superconductors is an introduction to organic conductors and superconductors and a review of the current status of the field. First, organic conductors are described, then the structures and electronic properties of organic superconductors are discussed, illustrated with examples of typical compounds. The book deals in detail with theories of the mechanism of superconductivity, and more briefly with spin-density waves. The design, principle, and synthesis of organic superconductors are also described. This second edition covers the research activities of the last few years.