Current service configuration of distinct Child and Adolescent Mental Health (CAMHS) and Adult Mental Health Services (AMHS) is considered the weakest link where the care pathway should be most robust. Transition-related discontinuity of care is a major health, socioeconomic and societal challenge for the EU.

The overall objective of the MILESTONE project is to improve transition from CAMHS to AMHS in diverse healthcare settings in Europe.

To improve the understanding of current transition-related service characteristics, and processes, outcomes and experiences of transition from CAMHS to AMHS using a bespoke suite of measures; to explore the ethical challenges of providing appropriate care to young people as they move to adulthood; to test a model of managed transition in a cluster randomized controlled trial (cRCT) for improving health, social outcomes and transition to adult roles; and to develop training modules for clinicians and policy guidelines.

Data will be collected via systematic literature reviews; bespoke surveys to CAMHS professionals, experts and other stakeholders; focus groups with service providers and users and members of youth and mental health advocacy groups; and a longitudinal cohort study with a nested cRCT in eight EU countries (Belgium, Croatia, France, Germany, Ireland, Italy, Netherlands, UK) involving over 1000 CAMHS service users, their parents/carers, and clinicians, with assessments at baseline, 9, 18 and 27 months.

First results are expected in 2016 with further major findings following in 2019.

The MILESTONE project will provide unprecedented information on the nature and magnitude of problems at the CAMHS-AMHS interface, and potential solutions to overcome these.

The authors have not supplied their declaration of competing interest.