Purpose: Despite advances in medical science, patient death and family bereavement are commonly encountered in adult intensive care units (ICUs). This is the first review to investigate the state of ICU bereavement support globally, and the availability and effectiveness of bereavement support interventions.Methods: A systematic review and narrative synthesis. Medline, CINAHL Plus, PsycINFO, Web of Science, EMBASE were searched and inclusion/exclusion criteria were applied. Included studies were appraised using relevant appraisal tools.Results: Fourteen papers formed the review; five of which were international surveys reporting variable bereavement practices and levels of support. A lack of training and resources were identified barriers. Nine papers reported the effectiveness of primarily discrete bereavement support interventions including: a personal memento, a handwritten condolence letter, a post-death meeting; storytelling, research participation, use of an ICU diary. One study evaluated a bereavement follow-up program. Generally, all identified interventions were well accepted by bereaved families.Conclusions: The reviewed evidence was weak, and findings were contextually bound. As such, it is difficult to make recommendations for the most acceptable and effective bereavement support intervention(s). Bereavement support in ICU needs further exploration and clinicians must be adequately trained and supported for the delivery of evidence-informed, culturally competent care.