The current study examines therapeutic processes during internet-based cognitive-behavioral therapy for social anxiety disorder. Participants will be randomized to either treatment or wait-list conditions. Participants in the wait-list condition will receive active treatment following the wait-list period.

Internet-based cognitive-behavioral therapy (iCBT) is an effective treatment for social anxiety disorder (SAD). However, little is known about the processes and mechanisms of change in this treatment. Compared to face to face (FTF) treatments, online interventions may operate through partially different mechanisms of change due to the text-based nature of the interaction and the reduced level of therapist involvement. The present randomized controlled trial will examine therapeutic processes during iCBT for SAD including the presence of sudden gains and their relationship to outcome, the relationship between anxiety and depressive symptoms along the course of treatment, changes in the therapeutic alliance and attrition from therapy. Moreover, we will compare iCBT for SAD with a wait-list control group and utilize weekly measurements of anxiety, depression, and SAD-related cognitions in both groups. This will facilitate comparison between temporal processes in both conditions and also shed light on processes occurring in wait-list conditions.

Inclusion Criteria:

• Meeting DSM-5 criteria for social anxiety disorder.
• Fluency in Hebrew
• Access to internet

Exclusion Criteria:

• Substance use disorders
• Past or present psychosis
• High levels of suicidality
• Changes in pharmacological treatment 3 months or less prior to the start of the trial
• Participation in other psychotherapeutic treatments during the trial