The physical decay of neighborhoods is associated with social conditions such as disease risk, poor mental health, and fear of crime. Researchers assessing neighborhood effects commonly operationalize neighborhoods via municipal boundaries such as U.S. Census Tracts, although more sophisticated analyses examine structures within a defined radius of respondents, typically 0.25-mile. This study verifies the 0.25-mile heuristic as a sound operational definition for neighborhood residential structures consequential to social conditions with measures of social contact with neighbors, perceptions of social capital, fear of neighborhood crime, and satisfaction with neighborhood quality of life. Deteriorating commercial structures cluster in smaller areas than deteriorating residential structures; however, the peak consequential radius appears to occur at 4 times the distance of residential structures. (Contains 1 table and 2 figures.)