This book presents a complete review of the solid-state chemistry of the materials behind the recent revolution in superconductivity research. Particular attention is paid to the main features that are necessary for the generation of high Tc superconductivity, for example, low dimensionality of the structure, a mixed valence of copper, hole delocalization and the role of lone-pair cations and alkaline earth elements. The relationships between the structures of the various oxide superconductors discovered so far are emphasized. Besides chemical and structural aspects, physical topics are included, such as electron transport properties in connection with oxygen nonstoichiometry and irradiation effects induced by neutrons, electrons and fast heavy ions. The numerous diagrams and photographs in this book simplify visualization of the structures and complement the clarity of the text.