Developing a culture of safety is a core element of many efforts to improve patient safety and care quality. This systematic review identifies and assesses interventions used to promote safety culture or climate in acute care settings. The authors searched MEDLINE, CINAHL, PsycINFO, Cochrane, and EMBASE to identify relevant English-language studies published from January 2000 to October 2012. They selected studies that targeted health care workers practicing in inpatient settings and included data about change in patient safety culture or climate after a targeted intervention. Two raters independently screened 3679 abstracts (which yielded 33 eligible studies in 35 articles), extracted study data, and rated study quality and strength of evidence. Eight studies included executive walk rounds or interdisciplinary rounds; 8 evaluated multicomponent, unit-based interventions; and 20 included team training or communication initiatives. Twenty-nine studies reported some improvement in safety culture or patient outcomes, but measured outcomes were highly heterogeneous. Strength of evidence was low, and most studies were pre–post evaluations of low to moderate quality. Within these limits, evidence suggests that interventions can improve perceptions of safety culture and potentially reduce patient harm.