The monopoly of a good enjoyed by a supplier over a marked area where no competitor exists. ‘In the literature on spatial monopoly, it is common to assume that the firm produced (or sold) only one good. This assumption, however, departs from the real world’ (Peng (2004) Southern Econ. J. 1 Jan.). ‘Spatial monopoly leads to the spatial impossibility theorem: no competitive equilibrium involving trade across locations exists in a homogeneous space’ (Stafford (2003) AAAG 93). Spatial monopolies happen when firms agree to split the market spatially, or through the privatization of public utilities, as in the case of the British Water Boards.