Historic England's Greater London Archaeological Advisory Service maintains the capital's Historic Environment Record and provides advice to 31 borough councils. Every London borough (except the City of London) has Archaeological Priority Areas (APA) defined in their local plan. They are areas defined for planning purposes where, according to existing information, there is significant known archaeological interest or particular potential for new discoveries.

These guidelines have been produced as part of a programme to review, revise and update the Archaeological Priority Areas across Greater London. They have been developed with the support of the Mayor of London and in consultation with borough councils, archaeological practices and interest groups.

The purpose of APAs is to provide a consistent framework for documenting archaeological interest for planning purposes. The new system will provide a sound evidence base and practical tool for strategic planning. The introduction of a 'tiered' system distinguishes those areas which are most significant from others which although still of interest are not quite so sensitive. This will help boroughs and developers narrow down the areas within their boroughs where archaeological interests may be affected.