variety of ways. These include statewide control of local land use decisions and statewide review of local land use decisions to determine their consistency with state guidelines; metropolitan-area-wide control of land use decisions within metropolitan-area boundaries or metropolitan review of local land use decisions; and state regulation of local land use, in particular the prohibition of specific exclusionary zoning practices. Another possibility would give developers the right to sue local jurisdictions that restrict their ability to provide low- and moderate-income housing, as in the Massachusetts Anti-Snob Zoning Law.

Zoning as a mechanism supports the system of small and fragmented local government that facilitates income segregation by jurisdiction (Mills and Oates, 1975). To the extent that such a system is associated with allocative efficiency by permitting the various local governments to respond to the relatively homogeneous preferences of their residents, as Tiebout (1956) and his followers argue, then reducing exclusionary zoning practices will adversely affect efficiency by promoting heterogeneity of preferences among the citizenry. The possibility of a trade-off between achieving optimal levels of allocative efficiency and reducing inequality of opportunity in metropolitan areas must be acknowledged.

Several states—Oregon, Florida, New Jersey, California, and Vermont, among others—have adopted state land use planning laws. Oregon's structure is probably the most elaborate and strongest in terms of the limits it places on traditional local government control of land use. The state has established 19 statewide goals and guidelines, 2 of which are particularly relevant. Goal 10 requires local government plans to provide for land uses that make housing available that meets the needs of households at all income levels. Goal 14 requires all urban areas in the state to designate urban growth boundaries outside of which land cannot be converted to urban use. In effect, all urban growth is to occur within these areas.

Local government plans, which are reviewed by the state land use authority, must conform to these goals. One study found that the state authority does indeed carefully review the plans and require revisions (Knapp, 1990). Indeed, Knapp notes that, of the 53 urban jurisdictions with populations over 5,000, only one plan satisfied the requirements for goals 10 and 14 on its first review. He concludes that Oregon is exercising a consistent policy favoring high-density development and requiring local governments to zone for their fair share of multiple-family and high-density housing and that, furthermore, this policy is not one that local governments would have adopted on their own.

As to the question of whether these developments have actually reduced the cost of housing and opened up the suburbs to low- and moderate-income households, Knapp observed in 1990 that there had been little research on this question. He contended that, although there had been a multifamily housing boom, "there