Abstract Background Hazardous alcohol use and alcohol use disorder (AUD) are highly prevalent among clients in mental health services, yet significant gaps remain in the adequate assessment of alcohol use and provision of appropriate alcohol interventions. The aim of this study was to conduct an exploration of (i) alcohol intervention elements used in mental health services and (ii) professionals’ reported barriers and facilitators in identifying and intervening with hazardous alcohol use and AUD. Methods Qualitative data were obtained by conducting semi-structured interviews among a purposive sample of 18 professionals from 13 different Dutch mental health services organizations (i.e., five integrated mental health organizations with addiction services, five mental health organizations without addiction services, and three addiction services organizations without mental health services). Transcripts were qualitatively analyzed using inductive thematic analysis. Results Identified alcohol intervention elements included conducting assessments, brief interventions, treatment, referrals of clients, collaborations with other parties, and providing information to professionals. Professionals mentioned nine barriers and facilitators in the identification and intervention with hazardous alcohol use and AUD, including three aspects of professionals’ behavior (i.e., professionals’ agenda setting, knowledge and skills, and attitudes), actions related to identification and intervening, client contact, collaboration with other parties, and three factors in a wider context (i.e., organizational characteristics, organizational resources, and governmental aspects). Conclusions Although diverse alcohol intervention elements are available in Dutch mental health services, it remains unclear to what extent these are routinely implemented. To better address hazardous alcohol use and AUD in mental health services, efforts should focus on enhancing alcohol training, improving collaboration with addiction services, providing ...