Objectives:Psychotropic drugs are frequently and sometimes inappropriately used for the treatment of neuropsychiatric symptoms of people with dementia, despite their limited efficacy and side effects. Interventions to address neuropsychiatric symptoms and psychotropic drug use are multifactorial and often multidisciplinary. Suboptimal implementation of these complex interventions often limits their effectiveness. This systematic review provides an overview of barriers and facilitators influencing the implementation of complex interventions targeting neuropsychiatric symptoms and psychotropic drug use in long-term care.Design:To identify relevant studies, the following electronic databases were searched between 28 May and 4 June: PubMed, Web of Science, PsycINFO, Cochrane, and CINAHL. Two reviewers systematically reviewed the literature, and the quality of the included studies was assessed using the Critical Appraisal Skills Programme qualitative checklist. The frequency of barriers and facilitators was addressed, followed by deductive thematic analysis describing their positive of negative influence. The Consolidated Framework for Implementation Research guided data synthesis.Results:Fifteen studies were included, using mostly a combination of intervention types and care programs, as well as different implementation strategies. Key factors to successful implementation included strong leadership and support of champions. Also, communication and coordination between disciplines, management support, sufficient resources, and culture (e.g. openness to change) influenced implementation positively. Barriers related mostly to unstable organizations, such as renovations to facility, changes toward self-directed teams, high staff turnover, and perceived work and time pressures.Conclusions:Implementation is complex and needs to be tailored to the specific needs and characteristics of the organization in question. Champions should be carefully chosen, and the application of learned actions and knowledge into practice is expected to further improve implementation.