The system in brief

There is just one planning system in England, but it operates on many levels
While your interest in, for example, a field may seem a very local concern, what will happen to that field depends on several levels of planning policy.
As shown below, local development is influenced by what happens nationally.
For example, whether a patch of land is filled with houses depends on which sites of land were allocated for housing in the local plan.
This in turn depends on how many houses the county structure plan said should be accomodated in the area, which in turn depends on what housing numbers the central Government allocated to the county or region.
The structure of influence is laid out below, starting with
- European directives and laws
- National planning legislation
- Primary acts of Parliament
- Secondary (regulations)
- National planning policy
- Planning policy guidance notes and minerals planning guidance notes
Guidiance notes are progressively being replaced by
- Planning policy and minerals policy statements
- Government circulars
- Government white papers
- Ministerial statements
These in turn influence
Regional plans and guidance
Regional planning guidance notes, progressively being replaced by
- Regional spatial strategies, including regional transport strategies
- (which influences) Other regional strategies
- Regional economic strategies
- Regional sustainable development frameworks (or equivalent)
- Others, such as cultural strategies
Regional plans then influence
- Higher tier (county and unitary council) plans
- Saved policies from county structure plans and unitary development plans (part I), being progressively replaced by regional spatial strategies
- Saved policies from minerals and waste local plans, progressively replaced by minerals and waste development framework
Which then influences
- Local development plans
Saved polices from existing local plans and unitary development plans (part II), being progressively replaced by local development frameworks, which are made up of
- Statutory development plan documents
- non-statutory supplementary planning documents.
Other 'material considerations' can be such things as changed circumstances, new information and overriding need.