This book reviews up-to-date knowledge on the biology of sole ( Solea senegalensis and S. solea ). These flatfish species are increasingly important in Europe both from the ecological and production point of view. This book is divided into two sections: A. general fisheries, aquaculture and engineering overviews; B. physiological, developmental, rhythmic, welfare and genetic aspects which will be of immense interest for the aquaculture industry. Experts, from both academia and research institutes, provide their expertise on sole biology.