Social anxiety disorder (SAD) may develop secondary to childhood attention deficit/hyperactivity (ADHD) in a subgroup of the patients with SAD. Patients pass through a number of identifiable stages of developmental pathways to SAD as they grow up. Patients with ADHD have maladaptive behaviours in social settings due to the symptoms of ADHD. These behaviours are criticized by their parents and social circle; they receive insults, humiliation and bullying. After each aversive incident, the individual feels shame and guilt. A vicious cycle emerges. The patients then develop social fears and a cognitive inhibition that occurs in social situations. The inhibition increases gradually as the fear persists and the individual becomes withdrawn. Patients start to monitor themselves and to focus on others' feedback. Finally, performative social situations become extremely stimulating for them and may trigger anxiety/panic attacks. If this hypothesis is proven, treatment of patients with SAD secondary to ADHD' should focus on the primary disease.