Participants Participants will be recruited from consecutive referrals to CADAT for treatment of SPOV. Clients will have a diagnosis of SPOV as defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) as their main presenting problem. They will be drawn from the CADAT waiting list, and if necessary from Improving Access to Psychological Therapy (IAPT) services at Southwark, Lambeth and Lewisham. These cases will be picked up by and treated at CADAT by qualified clinicians.