PURPOSE: The purpose of this paper is to explore the concepts of Swedish integrated health care, their state of development and interdependence, and, furthermore, evaluate whether the theoretical framework used improves the comprehension of why integrated health care arrangements endure or cease.

DESIGN/METHODOLOGY/APPROACH: The study is founded on descriptive data gathered from a literature search on integrated health care in Sweden. With inspiration from ecology theory, these data were analysed guided by a theoretical model based on a continuum of symbiotic effects, from antagonism to mutualism.

FINDINGS: The era of Swedish integrated health care started in the 1990s, when a kind of clinical network called chains of care was launched. At the beginning the chain of care development was predominantly surrounded by non-integrative conditions, which had a restraining effect on these efforts. Even so, it seems that chains of care are here to stay. This faith in chains of care can to some extent be explained by the crucial role they have as connectors in the emerging local health care systems. Thus, these systems need chains of care to evolve and chains of care seem to require the integrative framework of local health care to progress and endure. Integrated health care performance could be troublesome, unless such mutualistic conditions are in place. States of commensalism may also be promoted, but the advantages are unilateral and therefore there is a risk of disloyalty by the unaffected part, which, in turn, can create a breeding-ground for an antagonistic liaison.

ORIGINALITY/VALUE: A theoretical approach founded on what may be called "Health Care System Ecology" appears to enhance the understanding of the complex logic of integrated health care.