The tendency for particular retail establishments to cluster has been noted by several theorists on the subject of intraurban retail spatial structure. Hotelling, for example, in his classical essay on spatial competition, concludes that as “more and more sellers of the same commodity arise, the tendency is not to become distributed in the socially optimum manner but to cluster unduly.”1Rolph and Proudfoot provide empirical evidence of this tendency,2and Nelson supplies a rationale for it by his “principle of cumulative attraction.”3