Inorganic compounds of sulphur are widely found in living organisms, and are involved in steroid metabolism, diseases of the central nervous system, soil fertility, and the evolution of life. The importance of sulphur biochemistry, when this book was first published in 1970, had, however, only recently become apparent: this text brings together the scattered literature of the subject, and provides a balanced account of what was known. The enzymes concerned with the activation and transfer of sulphur groups are dealt with first. This is followed by a discussion of the metabolism of sulphur compounds in micro-organisms, animals, and plants. The clinical chemistry of sulphur and the economic importance of sulphur metabolism are considered; chapters on the chemistry, preparation and analysis of sulphur compounds are included. There is a guide to the nomenclature of the compounds.