Stocking hatchery-produced fish has been a standard component of fisheries management for over 100 years. This book discusses the production of hatchery fish used in aquaculture-assisted fisheries programs to help stabilize and recover endangered species.  For the most part, these programs have been unsuccessful, and a reason why is that the traditional approach to fish culture produces fish that are genetically and behaviorally ill-suited to help recover an imperiled species. The hatchery environment and management used to culture the fish makes them sub-viable in the wild.  Even if most of the augmented fish die, survivors that mate with wild fish lower the fitness of the endangered population, making the conservation program counter-productive.  Since traditional aquaculture programs have been shown to produce fish that are ill-suited to help recovery, a new way of producing fish is needed.  That new way is conservation aquaculture.  In conservation aquaculture, fish are raised in naturalized mesocosms that mimic the environment in which the endangered species lives.  Management is naturalized, so domestication does not produce genetic changes, and so fish develop a full and effective suite of behaviors that enable them to forage efficiently and detect and avoid predators when stocked. The conservation aquaculture management techniques described in the book can also be used to improve commercial and recreational fish stocking programs.