Objectives: The National Health Service has been moving towards integrated care for the best part of two decades to address the growing financial and service pressures created by an ageing population. Integrated healthcare systems (IHSs) join up health and social care services and have been established to manage the care of individuals with complex chronic conditions but with varied success. It is therefore imperative to conduct a Systematic Literature Review (SLR) to identify and understand the factors that influence their successful functioning, and ascertain the factor with the greatest influence, in order to ensure positive outcomes when establishing future IHSs.

Methods: Articles published between 1 January 1997 and 8 March 2020 were analysed from the following six databases: Healthcare Management Information Consortium, Nuffield Trust, Cumulative Index to Nursing and Allied Health Literature, PubMed, National Institute for Health and Care Excellence Evidence and Health Systems Evidence. Those deemed relevant after title and abstract screening were procured for subsequent review of the full-text article.

Results: Thirty-three finalised articles were analysed in this SLR to provide a comprehensive overview of the factors that influence the functioning of IHSs. Factors were stratified into six key categories: organisational culture, workforce management, interorganisational collaboration, leadership ability of staff, economic factors and political factors. Leadership was deemed to be the most influential factor due to its intrinsic and instrumental role in influencing the other key factors.

Conclusions: The findings of this SLR may serve as a guide to developing tailor-made recommendations and policies that address the identified key factors and thereby improve the functioning of present and future IHSs. Furthermore, due to both its overarching influence and the inadequacy of literature in this field, there is a strong case for further research exploring leadership development specifically for IHSs.