Classification is an important tool for scientific progress. It makes groups of individuals that share clinical symptomatology comparable and facilitates clinical communication. It should enable monitoring of treatment en guidance outcome through routine outcome measurement. But over the past decades classification systems have become increasingly popular with health and governmental authorities and insurance companies. The classification systems have acquired a fourth label that of a passport that gives access tot services. This should be a matter of concern for professionals and scientists in the field as it biases the primary scientific purpose of the exercise. ICD 10 and DSM IV and unfortunately also DSM V in progress have special sections for disorders occurring mostly in children and adolescents. This is an unfortunate categorization as most of the conditions met in childhood are in fact developmental disorders that persist well into adulthood. In this presentation the necessity for multilayer (genetic – brain – neuropsychology – behavioural signs and environment) will be presented and a stron plea made for disclosing child and adolescent conditions from their separate categories towards more developmentally geared dimensional perspectives.