ABSTRACT: BACKGROUND:The last decade, there have been many initiatives worldwide to increase the number of organ donors. However, it is not clear which initiatives are most effective. The aim of this study is to provide an overview of interventions aimed at healthcare professionals in order to increase the number of organ donors. METHODS:We systematically searched PubMed, EMBASE, CINAHL, PsycINFO, and the Cochrane Library for English language studies published until April 24, 2019. We included studies describing interventions in hospitals aimed at healthcare professionals who are involved in the identification, referral, and care of a family of potential organ donors. After the title abstract and full-text selection, two reviewers independently assessed each study's quality and extracted data. RESULTS:From the 18,854 records initially extracted from five databases, we included 22 studies in our review. Of these 22 studies, 14 showed statistically significant effects on identification rate, family consent rate, and/or donation rate. Interventions that positively influenced one or more of these outcomes were training of emergency personnel in organ donation, an electronic support system to identify and/or refer potential donors, a collaborative care pathway, donation request by a trained professional, and additional family support in the ICU by a trained nurse. The methodological quality of the studies was relatively low, mainly because of the study designs. CONCLUSIONS:Although there is paucity of data, collaborative care pathways, training of healthcare professionals and additional support for relatives of potential donors seem to be promising interventions to increase the number of organ donors. TRIAL REGISTRATION:PROSPERO, CRD42018068185.