The hyperturbulent health care environment is causing health care organizations to create interorganizational relationships (IORs). This article reports on a study of 686 medical groups that assessed how 11 types of IORs affected 7 dimensions of organizational performance. Organizational performance was ascertained through self-reported questions about performance relative to local market competitors. Respondents believed that, to varying degrees, all IORs lead to a competitive advantage over local competitors in all seven performance categories. There was no consistent pattern for either loose or tight linkages to be associated with superior performance. Consequently, loose linkages may be preferable to tighter linkages (i.e., membership in a fully integrated delivery system) that require higher levels of resource commitment.