This is a qualitative study of participants who have taken part in a randomized controlled trial (RCT) of a new treatment protocol based on cognitive-behavioral therapy for adults with attention deficit/hyperactivity disorder predominantly inattentive presentation. The purpose of the qualitative study is to explore participant perceptions of taking part in the RCT to further develop and improve the new treatment protocol.

Inclusion Criteria:

• Principal diagnosis of ADHD inattentive presentation
• 18 years of age or older
• If on medication, it needs to be well-established since three months, and
• Prior psycho-educational intervention

Exclusion Criteria:

• Intellectual impairment
• Substance use disorder
• Difficulties in adherence to medical or other treatment
• Social and/or psychiatric problems to such an extent that they prevent focusing on treatment, or
• Simultaneous psychological treatment