This book discusses Specific Learning Disabilities (SLD), with a special attention to the biology of these diverse conditions. It highlights the large biological component in the pathophysiology of SLE and the contribution of new biological investigative tools to the understanding of SLD such as dyslexia and dyscalculia and to the evaluation of therapies. It also discusses the relatively unrecognized emotional aspects of SLD, and the sometime devastating effects thatthese conditions have on the life of affected subjects and their families, in and out of the classroom.