The study examined whether the efficacy of cognitive behavioral treatment for Social Anxiety Disorder for children and adolescents is increased if intervention addresses specific cognitive and behavioral factors linked to the development and maintenance of SAD in young people, over and above the traditional generic CBT approach. Participants were 125 youth, aged 8-17 years, with a primary diagnosis of SAD, who were randomly assigned to generic CBT (CBT-GEN), social anxiety specific CBT (CBT-SAD) or a wait list control (WLC). Intervention was delivered using a therapist-supported online program. After 12-weeks, participants who received treatment (CBT-SAD or CBT-GEN) showed significantly greater reduction in social anxiety and post-event processing, and greater improvement in global functioning than the WLC but there was no significant difference between CBT-SAD and CBT-GEN on any outcome variable at 12-weeks or 6-month follow-up. Despite significant reductions in anxiety, the majority in both treatment conditions continued to meet diagnostic criteria for SAD at 6-month follow-up. Decreases in social anxiety were associated with decreases in post-event processing. Future research should continue to investigate disorder-specific interventions for SAD in young people, drawing on evidence regarding causal or maintaining factors, in order to enhance treatment outcomes for this debilitating condition.