Background: The majority of psychopathology emerges in late adolescence and continues into adulthood. Continuity of care must be guaranteed in this life phase. The current service configuration, with a distinction between child/adolescent and adult mental health services (CAMHS and AMHS), impedes continuity of care. AIm: To map professionals' experiences with and attitudes towards young people's transition from CAMHS to AMHS and the problems they encounter. Methods: An online questionnaire distributed among professionals providing mental health care to young people (15-25 years old) with psychiatric disorders. Results: Five hundred and eighteen professionals completed the questionnaire. Decision-making regarding transition is generally based on the professional's own deliberations. The preparation was limited to discussing changes with the adolescent and parents. Most transition-related problems are experienced in CAMHS, primarily with regard to collaboration with AMHS. Respondents report that the developmental age should be leading in the transition-decision making process and that developmentally appropriate services are important in bridging the gap. Conclusion: Professionals in CAMHS and AMHS experience problems in the preparation of, and the collaboration during transition. The problems are related to coordination, communication and rules and regulations. Professionals attach importance to improvement through an increase in flexibility and more specialist services for youth.