Attention Deficit Hyperactive Disorder (ADHD) is linked to three main symptoms: hyperactivity, inattention and impulsivity. It is increasingly being acknowledged that these symptoms have a wide-reaching impact on a person's life. Adolescents with ADHD are six times more likely to be excluded from school, have difficulties turn taking, express anger more often, have poorer emotion regulation and self-report a lower quality of life. In adulthood, people with ADHD are more likely to develop mental health difficulties, and to experience unemployment, divorce and be imprisoned. It is thought that emotion regulation and poor social skills are key factors leading to increases in mental health difficulties and poorer long term social outcomes. This pilot trial will look at whether an intervention which aims to increase emotion regulation and social functioning is acceptable and feasible. The intervention will be an adapted Dialectical Behaviour Therapy (DBT) skills group with an ADHD focus. DBT is an approach that aims to provide skills to assist an individual identify what they are feeling and change what they do in response to that feeling. For example, if an individual feels anger and the urge to be aggressive, DBT helps them to problem solve and find a more effective way of responding to their anger. Also, if an individual wants to communicate a relational need to others DBT helps them think about the most effective actions they can take to achieve this outcome. The intervention will be developed in collaboration with adolescents with ADHD. The intervention will then be delivered at the child and adolescent outpatient clinic site they received their diagnosis from. All participants will have a confirmed diagnosis of ADHD. Pre and post measures will be collected and reported on. The research team hope to commence recruitment in July 2023 and finish all data collection by 31st March 2024.

Inclusion Criteria:

• Diagnosis of Attention Deficit Hyperactive disorder (using either DSM 5, DSM-IV, or ICD-10 - F90)
• Age 13-16 years
• Likely to benefit from DBT skills and can safely access/ engage in group interventions as assessed by clinical team [for intervention part]

Exclusion criteria:

• A low enough proficiency in written and spoken English that they would be unable to engage in the content of the group.
• Have not recently changed their medication in the last 2 weeks*, commenced a new medication in the last 2 weeks* or are receiving additional concurrent psychological intervention. (*calculated from the start of the intervention).
• The identified participant has recently taken part in another research trial and are at risk of research burden.
• Pose a risk to others in the group

There is no plan to make individual participant data available to other researchers.