green belts have been implemented across the oecd albeit with decidedly mixed results as part of national urban policy in the united kingdom or national spatial planning in the netherlands as well as around numerous cities including vienna barcelona budapest berlin hong kong seoul tokyo toronto vancouver chicago sydney and melbourne kamalchaoui and sanchezreaza in both japan and korea the national government defines zoning categories for municipalities that orient the form and intensity of local land uses in korea for instance zoning reform in included revisions to encourage mixeduse and transitoriented development oecd a a global survey of planning practices in the mid s found almost universal acceptance of comprehensive master planning or its equivalent friedmann typically cities are mandated by national governments to produce master plans that specify future land uses and circulation patterns