A Unitary Development Plan (UDP) is an old-style development plan prepared by a metropolitan district and some unitary Local Planning Authorities that contains policies equivalent to those in both a structure plan and a local plan. By virtue of specific transitional provisions, these plans will continue to operate for a time after the commencement of the new development plan system. It is a statutory document that sets out the council’s planning policies that will be used to guide development, conservation, regeneration and environmental improvement activity.

The Unitary Development Plan is used at all stages of production and is reliant on criteria-based policies. Often contentious sites are proposed, which may generate significant opposition to the proposal. The existing system of UDPs makes it very difficult to provide a clearer framework.