Supporting patients in exerting choice over their treatment is a central aspect of modern healthcare. In Improving Access to Psychological Therapies (IAPT) services, then patients treated at step 2 are only and always offered cognitive-behaviourally informed guided self-help (GSH), when they are deemed suitable for treatment at step 2 of IAPT services (termed CBT-GSH). Step 2 interventions are guided self-help (GSH) delivered by Psychological Wellbeing Practitioners (PWPs). Recently, a new type of GSH has been developed and found to be feasible and effective in IAPT services - this is called cognitive-analytic guided self-help (CAT-GSH). This research aims to test the efficacy of CAT-GSH by comparing outcomes over time achieved in both types of GSH and interviewing participants about their experience of the GSH. The methodology to support patient choice is a patient preference trial. In this method, then patients that meet inclusion criteria for the trial are offered and choose between either CAT-GSH and CBT-GSH. Those patients that are unconcerned with the type of treatment are randomised to either CAT-GSH or CBT-GSH. The primary outcome measure is the Beck Anxiety Inventory. No changes to the standard practice of the PWPs will occur during the trial, the trial will be situated in a standard IAPT service and be a therefore conducted in a routine practice setting.

Inclusion Criteria:

• patients have self-referred or been referred by their GP or other health or social care professional for a step 2 intervention for treatment of a common mental health problem,
• patients meet criteria for an anxiety disorder on MINI screening interview assessment and also met caseness on the BAI (as defined by a score of >10 on the BAI at assessment).
• Patients want to engage in GSH to address the anxiety disorder
• patients are motivated to engage in treatment and can attend six sessions of face-to-face GSH.

Exclusion Criteria:

• engaging in any another IAPT step 2 interventions.
• Do not meet criteria for an anxiety disorder as defined by the MINI and the BAI score.
• Meet criteria for depression and a comorbid anxiety disorder, as identified by the BAI and MINI, where the depression is more severe and is the patient's main concern.
• Have a severe/chronic mental health problem and are already involved in psychiatric or secondary care mental health services.
• Have substance misuse issues that would interfere with engagement with the GSH.
• Have a diagnosed learning disability that precludes engagement in GSH.
• Have a diagnosis of social phobia or PTSD