Adolescence and young adulthood is a developmental period characterized by highly dynamic changes in neurobiological, somatic and psychosocial functions as well as self-concepts and demands from society. As for every chronic disorder it can be extremely challenging for health care providers to keep patients with ADHD in this age group within the medical system while transition from child and adolescent to adult health care system. This may be accounted for by reasons, which are inherent to this developmental period but also due to barriers or circumstances of the medical system, that hamper a smooth transition from child and adolescent to adult mental health care. However, in comparison to transition processes for adolescents with chronic somatic disorders, transition processes for mental health services has received much less attention in general and for ADHD in special, to date. There is only limited research investigating transition of patients with ADHD from child to adult services. Though recommendations for the transition of ADHD patients exist (e. g. NICE guidelines), these are often rather general prescriptions than ground level algorithms on how to achieve this effectively in clinical routine care. The aim of the talk is to provide an overview about available empiric data related to this topic.