This article explores a key policy shift in the new Hampstead Neighbourhood Plan 2025-2040: the emphasis on retrofitting and sustainability. It examines how the Plan encourages energy-efficient improvements to existing buildings, reflecting the "increased urgency of demands for energy efficiency created by climate change". The piece contrasts this "fabric-first" approach with the demolition-and-new-build model typical of large regeneration schemes. It features case studies of successful retrofits in the conservation area and analyses the policy levers the Forum can use to promote considerate construction, better water run-off, and lower embodied carbon in new projects.