IPA-model HMOs are now the dominant organizational structures for delivering "managed care" in the United States. Are they taking advantage of opportunities to support physician practices in ways that arguably could improve care? In this paper we report the findings from a survey of generalist and specialist physicians in nineteen health plans. Not surprisingly, we found that generalists are much more likely than specialists are to be the target of health plans' efforts to support care delivery. However, our survey data indicate that these opportunities generally are not being fully exploited; also, efforts that plans do make to provide information to support care often are not seen as useful by physicians.