There has been increased interest in recent years in the practicalities of the conservation, rehabilitation and improvement of salmonid habitat. The author has spent most of his career in studies of the ecology of salmon and trout. He has used his experience to bring together and summarise findings in many scientific publications on the ecology of riverine salmonids in a form that is comprehensible without sacrificing scientific rigour. This information is the essential basis for habitat improvement. The latter part of the book deals in detail with the manner in which mans varied activities impinge upon the well-being of the salmonids and this leads on to a consideration of the general philosophy underlying practical measures for conservation and rehabilitation.