The overall improvement test

The UK Government Guidance "Summary: Planning and Infrastructure Bill, Government Amendments to Part 3 (Lords Committee Stage)" updated 19 September 2025 describes the overall improvement test:

"The overall improvement test is the existing test that the Secretary of State must consider to be passed before they can approve an Environmental Delivery Plan (EDP). The government has always been clear that it is one of the key environmental safeguards in the new system and, as such, it is vital that there is confidence in its operation.

"The amendment we are tabling clarifies this test. It removes any risk of ambiguity by making it clear that the Secretary of State can only approve an EDP where the effect of the conservation measures will materially outweigh the negative effect of development on the conservation status of each identified environmental feature. This provides further assurance for communities and developers that outcomes will be delivered, and that the actions taken under an EDP must lead to a material improvement for the relevant environmental feature."

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