This study evaluates two types of internet-based treatments for generalized anxiety disorder and two types of support. The treatments are a predetermined program for generalized anxiety disorder and a self-selected treatment. The different types of support are either a weekly contact trough a secure message system or support on demand.

Generalized anxiety disorder (GAD) is characterize by and excessive and uncontrollable worry that is present more days than not. The disorder is best described as a chronic condition with periods with more or less symptoms. The disorder is highly disabling with low quality of life for the individual and is associated with and high costs for society. Previous studies on internet-based cognitive behavior therapy for GAD has shown positive effects but there are still room for improvement.

The aim of this study is to evaluate two different internet-based treatments as well as two types of support through the use of a factorial design. The participants will be recruited trough advertising. After registration on the study's website the potential participants will be asked to answer screening questionnaires and demographic data for an initial screening. Those meeting inclusion criteria will be contacted for a diagnostic interview based Mini-International Neuropsychiatric Interview (M.I.N.I.). If meeting the study's inclusion criteria and not the exclusion criteria the participant will be included in the study and randomized to one of the four arms. The four arms are: Predetermined treatment program with weekly support, Predetermined treatment program with support on demand, Self-selected treatment with weekly support, Self-selected treatment with support on demand.

The predetermined treatment program is designed for treatment of worry and generalized anxiety disorder. It is based on newer forms of cognitive behavior therapy and includes mindfulness and acceptance. In the self-selected treatment the participants will select treatment interventions with the help of a manual and encouraged to choose interventions that they feel address their specific problems. The interventions that will be available are all based on standard cognitive behavior therapy techniques. The weekly support will be scheduled and delivered by clinical psychology students under supervision. This contact will be based on reports from the participants on the weeks work with the program and exercises. The support on demand will be also be delivered by clinical psychology students under supervision. This support takes place if and when the participant ask for support. Treatment will be 8 weeks long and both treatments will be delivered through the same platform. Contact with the participants will be trough written messages on a secure platform.

After the eight weeks of treatment the participants will be asked to answer the same measures as before the treatment as well as questions regarding how they experience the treatment. Follow up data will be collected at later points.

Inclusion Criteria:

• At least 18 years old
• fulfilling criteria for generalized anxiety syndrome
• 45 points or more on PSWQ
• Able to read and write in Swedish
• Have daily access to a computer and internet

Exclusion Criteria:

• Alcohol or substance abuse
• Acute suicidal
• Ongoing psychological treatment
• Ongoing medication for anxiety or depression that is planned to be adjusted during the time of the treatment given in the study
• Complex psychiatric illness that highly disabling