Rainbow trout can be an excellent economic proposition for farming in temperate waters. The husbandry needed is simpler, and the fish take a year less than Atlantic salmon to grow to an equivalent size. This handbook is a standard guide for trout farmers. It covers the latest developments and new opportunities, particularly for rainbow trout farming in the sea. The design and construction of trout farms is described and every stage of trout production is dealt with in detail: hatching and fry production; fish feeds and feeding; hygiene and the prevention and treatment of diseases, and the management of brood stock. Processing and marketing are discussed together with ways and means of increasing profitability. Special attention is given to the prevention of pollution and protection of the environment.