Introduction: To implement an integrated health care system is not an easy task and to ensure its sustainability is yet more difficult. Aim: Discuss how a structurationist approach can shed light on the stakes of these processes and guide the managers of such endeavours. Theory and method: Structuration theory [1] has been used by numerous authors to cast new light on complex organizational phenomena. One of the central tenets of this theory is that social systems, such as integrated health care systems, are recurrent social practices across time-space and are characterized by structural properties which simultaneously constrain and enable the constitutive social actors who reproduce and transform the system through their practices. We will illustrate our theoretical standpoint with empirical material gathered during the study of an integrated health care system for the frail elderly in Quebec, Canada. This system has been implemented in 1997 and is still working well in 2010. Results and conclusion: To implement an integrated health care system that is both effective and sustainable, its managers must shrewdly allow for the existing system and progressively introduce changes in the way managers and practitioners at work in the system view their role and act on a daily basis.