Background: Middle managers within healthcare hold a unique position between senior leadership and frontline staff, and may hold a pivotal function in the implementation of quality improvement (QI) projects. This review aims to explore what is known about healthcare middle managers' role in implementing QI initiatives, and to determine if consensus around their role exists amongst middle managers and other healthcare stakeholders alike. Methods: A review of the current literature, limited to the English language was undertaken using the databases CINAHL (ESBSCO), PsychInfo, Cochrane, Medline (OVID) and Google Scholar. Of the 2473 articles the search yielded, data was extracted from 16 articles that met the authors' inclusion criteria. Results: There is scarcity of empirical literature surrounding healthcare middle managers' role in project implementation, and limited consensus in regards to role descriptors is identified. There is general agreement that middle managers have a role in mediating between strategy and day-to-day activities, acting as the primary supporter of frontline staff, and serving as a knowledge broker. However, disagreements about their role are apparent with discrepant perceptions held by the broader stakeholder group (physicians, frontline staff, and senior level leadership) and amongst middle managers themselves. Conclusions: A limited understanding exists around the specialized role of middle managers within this context, and could be a contributing barrier to QI project implementation. It is suggested that a lack of role clarity amongst middle managers is evident and may be attributed to various contexts and implementation strategies used in quality improvement (QI).