Translating potential into policy and then into reality has proved difficult, however. In part, the problem lies with defining the ideal urban form. In contrast, low-density cities are land intensive but may provide other amenities such as open space. Even more vexing has been the relative failure of governments to successfully guide urban form, even with detailed master plans and regulatory systems. Land use planning is notoriously difficult.
Regulatory tools can have unintended impacts.
In cities in developing countries, zoning and regulations have the unintended effect of putting the land out of the financial reach of the majority of residents. This section explores how land use planning can improve urban environmental quality. Prescriptions for better urban land use are not the same for all cities. In cities in developing countries, land use issues must still focus on improving access to serviced urban land for the poor, for it is at this level that the greatest toll on the environment and human health is being taken. How cities choose to allocate and direct this land, however, can have an impact on future environmental conditions.