 Single-use zoning is a basic model that has not evolved to create appropriate solutions for the increasing complexity of social, political and environmental challenges in cities, according to critics.Problems affiliated with Euclidean-style zoning policy include urban sprawl, urban decay, environmental pollution, racial and socioeconomic segregation, negative economic impacts and an overall reduced quality of life.Land use regulations associated with a high separation of land uses have also been criticized as being fraught with legal obstacles to rehabilitating neighbourhoods affected by the aforementioned problems (such efforts are often referred to as urban rehabilitation or urban renewal).