To investigate various types of how to conduct a standardized CBT-protocol, all therapists are tutored in peer dyads (tandem peer tutoring). Immediate before sessions 1 to 5, the therapists are required to contact the tandem-partner face-to-face or via self-phone to deliberate the forthcoming session by a 5 to 10 minute brief communication (primings; for a comparable procedure see Flückiger & Grosse Holtforth, 2008). The tandem peer tutoring are grouped in three conditions: