The current study examines the efficacy of intensified group therapy for social anxiety disorder with fear of blushing. Task concentration training (TCT) and cognitive therapy (CT) were applied during one weekend and compared with a waiting list condition in a randomized controlled trial including 82 patients. On a second weekend, another intervention was added (resulting in TCT–CT and CT–TCT sequences) to examine order effects. Task concentration training and CT were both superior to the waiting list and equally effective after the first therapy weekend. Also, no differences were found between the sequences TCT–CT and CT–TCT at post‐assessment. At 6‐ and 12‐month follow‐up, effects remained stable or further improved. At the 6‐month follow‐up, remission rates in completers, established by diagnostic status, were between 69% and 73%. Intensified group therapy is highly effective in treating social anxiety disorder with fear of blushing. Group formats for patients sharing a common primary concern may contribute to the dissemination of cognitive–behavioural therapy. Copyright © 2015 John Wiley & Sons, Ltd. Key Practitioner Message: This study focuses on blushing from fearful individuals within the SAD spectrum to improve evidence for treatment efficacy in those whose social fears are centred around observable bodily sensations. This study integrates task concentration training into the SAD model of Clark and Wells to combine two evidence‐based treatments for SAD under one treatment model. This study uses an innovative format of brief, intensified group therapy, conducted on two full‐day weekend group sessions delivered over two weekends, with strong observed effect sizes.