Innovations in Practice: Dialectical behaviour therapy for adolescents: multisite implementation and evaluation of a 16-week programme in a public community mental health setting Daniel Flynn 1 , Mary Kells 2 , Mary Joyce 3 , Paul Corcoran 4 , Conall Gillespie 3 , Catalina Suarez 3 , Michaela Swales 5 & Ella Arensman 3 1 Cork Mental Health Services, Cork Kerry Community Healthcare, Health Service Executive, St Finbarr’s Hospital, Cork, 2 Cork Mental Health Services, Cork Kerry Community Healthcare, Health Service Executive, Cork, 3 National Suicide Research Foundation, University College Cork, Cork, 4 School of Public Health, University College Cork, Cork, Ireland 5 Betsi Cadwaladr University Health Board & North Wales Clinical Psychology Programme, School of Psychology, Bangor University, Bangor, UK Background: Dialectical behaviour therapy for adolescents (DBT-A) is an intervention with a growing evidence base for treating adolescents with emotional and behavioural dysregulation. This study describes the imple- mentation and effectiveness of 16-week DBT-A across multiple sites in publicly funded child/adolescent mental health services (CAMHS) in Ireland. Method: The Consolidated Framework for Implementation Research was used to guide this national implementation. Fifty-four clinicians from seven CAMHS teams completed DBT training and delivered the 16-week DBT-A programme. Eighty-four adolescents with emotional and beha- vioural dysregulation participated in the intervention and outcome measures were administered at preinter- vention, postintervention and 16-week follow-up. Results: Significant reductions on all outcome measures were observed for DBT-A participants including presence and frequency of self-harm, suicidal ideation and depression. Reductions in the number of acute inpatient admissions, bed days and emergency department vis- its were also reported. Conclusions: DBT-A can be successfully implemented in CAMHS settings and yield posi- tive outcomes for adolescents with emotional and behavioural dysregulation. Key practitioner messages • DBT teams can be successfully established in CAMHS as part of a coordinated implementation approach. • DBT-A is a treatment approach which can be implemented in real-world public health settings. • Positive outcomes have been reported for DBT-A for adolescents who self-harm and/or have suicidal ideation or behaviour. • DBT-A was associated with a reduction in health service utilisation at postintervention and at a 16-week follow-up period. Keywords: Dialectical behaviour therapy; adolescents; implementation; community settings; self-harm; depression Introduction International community studies report that around 10% of adolescents have self-harmed (Hawton, Saun- ders, & O’Connor, 2012). In Ireland, a national registry of self-harm, which records self-harm presentations at hospital emergency departments, reports high rates for young people with peak rates reported for females aged 15–19 years (Griffin et al., 2016). Despite increasing rates of self-harm in young people, specialised treat- ments for adolescents are limited (Hawton et al., 2015). Dialectical behaviour therapy for adolescents (DBT-A) is a treatment which was initially developed for suicidal adolescents with chronic emotional dysregulation (Miller, Rathus, & Linehan, 2007). DBT-A has been delivered to adolescents with self-harm and suicidal behaviour with positive outcomes reported in outpatient and community settings (Fleischhaker et al., 2011; James, Taylor, Winmill, & Alfoadari, 2008; Mehlum et al., 2014; Rathus & Miller, 2002; Woodberry & Pope- noe, 2008). In Ireland, by 2013, clinicians working in child and adolescent mental health services (CAMHS) began to consider DBT-A as a treatment for the increasing num- ber of self-harming adolescents presenting to their ser- vice. While there was growing interest in DBT provision for adults and adolescents in Ireland, challenges regard- ing securing of funding for individual team training and awareness of how best to establish DBT in community services continued. A proposal was put forward to a © 2018 Association for Child and Adolescent Mental Health. Published by John Wiley & Sons Ltd, 9600 Garsington Road, Oxford OX4 2DQ, UK and 350 Main St, Malden, MA 02148, USA Child and Adolescent Mental Health 24, No. 1, 2019, pp. 76–83 doi:10.1111/camh.12298