This handbook gives an extensive account of the significant aspects of ADHD. Thus taking into account the different forms of this disorder over a life-span and supporting the quality management in treating the affected.The contributions are based on the wide knowledge of the editors and leading experts in research, clinical practice and evidence based medicine. Basics of definition, classification and epidemiology and scientific findings on the causes are communicated as well as differentiated descriptions of the various aspects of clinic, examination, therapy and course of ADHD.