The aim of the current study is to provide a short overview on autism, attention deficit hyperactivity disorder (ADHD) and Tourette syndrome. According to international data, the prevalence of autism is 2-60/10000 and the symptoms persist during the entire life; the prevalence of ADHD among children and adolescents is 2,4-12,0% and the symptoms cause problem in 30-50% in adults as well; while the prevalence of tic disorder is 1-6,6% among children and adolescents and the symptoms persist in 10% in adulthood. According to Hungarian data, these disorders are relatively rare in adult psychiatric practice. Presenting case reports of adults with autism, ADHD and Tourette syndrome, we would like to demonstrate the symptoms, treatment possibilities of these disorders and how they can influence the patients' quality of life.