Attention deficit hyperactivity disorder is one of the most common neuropsychiatric conditions in childhood and adolescence. Its diagnosis and treatment have been of interest and controversy, both in the scientific community and in the general population. Current scientific evidence supports the formulation of the diagnosis and treatment and better understanding of etiology and pathophysiological mechanisms. From a neurobiological perspective, genetic factors seem strongly determinant in most cases, but there are also environmental factors that influence the genesis, expression and clinical evolution. In addition to conducting a review of clinical and neurobiological evidence refuting a series of widely disseminated misconceptions, this article discusses the need of comprehensive diagnosis and treatment, incorporating biopsychosocial variables in order to avoid misconstrued labels that may affect children and adolescents. Both diagnosis and treatment should be at service of promoting the highest potential of ADHD children and youngsters.