The article has two parts. Part one deals with some historical developments in the field of special education in Norway. There has been a change in formulated policy from a clearly segregated system, then integration and mainstreaming and now intentions about inclusion as an ideal. The second part is about children with behavioural difficulties and especially children diagnosed with ADHD (Attention Deficit and Hyperactivity Disorders) and how they are treated within the education system. Knowledge about these children's situation is not very well developed or widespread in the Norwegian education system. The numbers of children with an ADHD diagnosis vary a lot between schools. Both diagnosis and treatment connected to ADHD have been highly controversial in Norway, as in many other countries. The gap between ideals and realities is a striking element in special education in Norway and also for these children. The inclusion criteria have not been met. The reasons for this are discussed.