Public health researchers have provided a growing body of evidence on the salutary effects of social capital for individual well being. The importance of these findings for social epidemiology, however, may have precluded so far a full examination of the complex association between neighborhood social processes and the well being of individual residents, including the often acknowledged potential "downside" of social capital. In this study, we examine the association between attachment to community, an indicator of social capital, in a sample of African American parents, and the presence of behavior problems in their preschool children. Participants were recruited from a socioeconomically diverse set of neighborhoods. Attachment to community was assessed using a multi-item scale comprised of two subscales, general sense of community and how well one knew one's neighbors. Results indicated that the association between how well a parent knew her neighbors and the presence of child behavior problems differed depending on the degree of economic impoverishment of the neighborhood. In wealthy neighborhoods, children whose parent reported knowing few of the neighbors had higher levels of internalizing problems such as anxiety and depression compared to those who knew many of their neighbors. In contrast, in poor neighborhoods, children whose parent reported knowing few of the neighbors had lower levels of internalizing problems compared to those who knew many of their neighbors. These results are discussed in terms of furthering the study of the contextual nature of the social capital in explaining community inequalities in mental health among children.