PurposeThis paper aims to examine effective diagnostic and treatment pathways for attention deficit hyperactivity disorder (ADHD) in prison settings given the high prevalence of ADHD and comorbidities in the prison population.Design/methodology/approachTwo studies were carried out in two separate prisons in London. Firstly, data were collected to understand the prevalence of ADHD and the comorbidities. The second study used quality improvement (QI) methodology to assess the impact of a diagnostic and treatment pathway for prisoners with ADHD.FindingsOf the prisoners, 22.5% met the diagnostic criteria for ADHD. Nearly half of them were screened positive for autistic traits, with a higher prevalence of mental disorders among prisoners with ADHD compared to those without. The QI project led to a significant increase in the number of prisoners identified as requiring ADHD assessment but a modest increase in the number of prisoners diagnosed or treated for ADHD.Originality/valueDespite various challenges, an ADHD diagnostic and treatment pathway was set up in a prison using adapted QI methodology. Further research is needed to explore the feasibility of routine screening for ADHD in prison and examine at a national level the effectiveness of current ADHD prison pathways.