This book, published in two volumes, provides the most comprehensive review of lamprey biology since Hardisty and Potter’s “The Biology of Lampreys” published more than 30 years ago. This second volume offers a synthesis of topics related to the lamprey gonad (e.g., lamprey sex ratios, sex determination and sex differentiation, sexual maturation, and sex steroids), the artifical propagation of lampreys, post-metamorphic feeding and the evolution of alternative feeding and migratory types, the history and status of sea lamprey control in the Laurentian Great Lakes and Lake Champlain, and an overview of contributions of lamprey developmental studies for understanding vertebrate evolution.