The present study examined the relationship between characteristics of neighborhoods (with set physical boundaries and relatively homogeneous populations) and personal well-being as mediated by sense of community and neighboring behavior. A randomly selected representative sample of 345 residents living in non-apartment dwellings in Winnipeg, Canada, completed a mail survey that included created measures of neighboring and sense of community and the General Health Questionnaire. Results demonstrated that sense of community mediates the relationship between neighborhood stability (as defined by the marital status and mobility) and residents' well-being. The frequency of engaging in neighboring behavior was not directly predictive of residents' sense of personal well-being, but was predictive of increased sense of community. Consistent with previous research, findings highlight the importance of building a sense of community among residents in a neighborhood. Implications of findings for neighborhood planning are discussed. (Contains 2 tables and 2 figures.)