To control development on a single parcel that would escape subdivision review. Especially important for commercial or industrial developments or for residential developments with multiple structures. Can include aesthetic controls. County and regional review may be required if near municipal boundary, county, state highway or park, state or county public building site.

To go beyond zoning to address environmental and traffic consequences and unsightly design. Can have more or less detailed standards. Can require open space or fee-in-lieu of open space. Clustering can be offered, sometimes required.

Specific standards needed.

Can influence neighborhood design. Can include standards for connectivity and response to environmental constraints. Can include aesthetic considerations. When coordinated with other developments, can increase overall level of road-network connectivity in a larger area.