More and more educators and social workers are increasingly confronted with behaviorally troubled children and adolescents in their respective fields and are reaching their limits in handling these situations. Public media also portray a negative image of today's youth: there seem to be more frequent rule violations, conflicts, and outbreaks of violence. The rise in diagnoses such as ADHD, Asperger's syndrome, bipolar disorder, or the mood disorder Disruptive Mood Dysregulation Disorder (DMDD) reinforces this impression. But have mental disorders really increased? Or has the sensitivity towards these behaviors changed instead? In this volume, the contributors examine the trend of increasing psychopathological differentiation and medicalization of problematic and disruptive behavior, starting from fundamental assumptions.