Integrated health systems are considered part of the solution to the challenge of sustaining Canada's healthcare system. This systematic literature review was undertaken to guide decision-makers and others to plan for and implement integrated health systems. This review identified 10 universal principles of successfully integrated healthcare systems that may be used by decision-makers to assist with integration efforts. These principles define key areas for restructuring and allow organizational flexibility and adaptation to local context. The literature does not contain a one-size-fits-all model or process for successful integration, nor is there a firm empirical foundation for specific integration strategies and processes.