<P> The model has been challenged by many contemporary urban geographers . First, the model does not work well with cities outside the United States, in particular with those developed under different historical contexts . Even in the United States, because of changes such as advancement in transportation and information technology and transformation in global economy, cities are no longer organized with clear "zones" (see: Los Angeles School of Urban Analysis). </P> <Ul> <Li> It describes the peculiar American geography, where the inner city is poor while suburbs are wealthy; the converse is the norm elsewhere . </Li> <Li> It assumes an isotropic plane--an even, unchanging landscape . <Ul> <Li> Physical features--land may restrict growth of certain sectors; hills and water features may make some locations unusually desirable for residential purposes . </Li> </Ul> </Li> <Li> Commuter villages defy the theory, being a distant part of the commuter zone . </Li> <Li> Decentralization of shops, manufacturing industry (see Industrial suburb), and entertainment . </Li> <Li> Urban regeneration and gentrification--more expensive property can be found in formerly' low class' housing areas . </Li> <Li> Many new housing estates were built on the edges of cities in Britain . </Li> <Li> It does not address local urban politics and forces of globalization . </Li> <Li> The model does not fit polycentric cities, for example Stoke - on - Trent . </Li> </Ul> <Li> It describes the peculiar American geography, where the inner city is poor while suburbs are wealthy; the converse is the norm elsewhere . </Li> <Li> It assumes an isotropic plane--an even, unchanging landscape . <Ul> <Li> Physical features--land may restrict growth of certain sectors; hills and water features may make some locations unusually desirable for residential purposes . </Li> </Ul> </Li>

In concentric zone model of burgess the fifth ring is occupied by