This study, based on a random-digit-dialing telephone survey of adults in Maine, New Hampshire, and Vermont, uses ordinary least squares regression to examine a relatively neglected element in the sociological literature on environmental concern, namely, the influence of an individual's social capital on the formation of environmental attitudes. We argue that it is those individuals with a greater diversity of social connections who are most likely to be influenced by ecological perspectives grounded in conservation and environmental protection. Controlling for other theoretically relevant variables, we regress an index of environmental concern that gives special emphasis to environmental-economic trade-offs on our measures of relational and community social capital. While confirming much of the earlier work in this area, our model provides evidence that connections to other people play an important role in determining individual concern for the environment. Specifically, the number of respondents' “weak ties”—that is, not their closest relationships—and the average occupational status of respondents' social ties, in general, were both positively correlated with environmental concern. Additionally, one of our three measures of community social capital, the number of visits from friends over the past month, was statistically significant and negatively correlated with environmental concern.