The subcultural theory contends that urbanism independently affects social life—not by destroying social groups as the determinist view of the ecological school suggest, but instead by helping to create and strengthen them. It creates new social groups. The most significant social consequence of community size is the proportion of diverse subcultures.

Like compositional theory, the subcultural theory maintains that intimate social circles persist in the urban environment. But, like the ecological theory it maintains that ecological factors do produce significant effects in the social orders of communities, precisely by supporting the emergence and vitality of distinctive subcultures—interact with those with relatively distinct set of beliefs and behaviours.