Book excerpt: This book presents a definitive volume on perch and related fish. In the introduction an outline is given on the characteristics of the order Perciformes, the suborder Percoidea and the family Percidae. The bulk of the book is devoted to a review of the biology of perch, walleye and zander. Special emphasis is placed on external controlling factors of body processes (in particular temperature), on population dynamics and on fisheries. The final part of the book considers other genera of the Percidae including the ruffes, darters and zingels which although economically unimportant have biological significance.