The government recognises the value of formally approved guidance to support timely, safe and effective PFAS remediation, and is taking forward work to develop this in a way that reflects the current and evolving evidence base. In line with the UK PFAS Plan, EA is developing technical guidance for regulators, industry and landowners on the investigation, assessment and management of PFAS contamination across environmental media. The guidance will support riskbased decision making, improve consistency across regimes (including planning, environmental permitting and contaminated land), and help to avoid unintended consequences such as pollutant transfer or incomplete treatment. This work builds on a growing evidence base, international best practice and emerging research on PFAS remediation. EA has already produced substantial tools to support consistent regulatory decisions, including the 2024 Lines of Evidence framework and recent evidence reviews on soil stabilisation and permeable reactive barriers, which together enable structured assessment of effectiveness, sustainability, uncertainty and longterm risk. Further work is needed to translate this evidence into clear, accessible guidance that can be applied consistently across Environmental Permitting Regulations, the contaminated land regime, and the planning system. This includes clarifying expectations for site characterisation, treatability testing, verification and longterm monitoring, and addressing residual liabilities where PFAS is immobilised rather than destroyed. Given the persistence of PFAS, historic contamination and slow movement through soils and groundwater, improvements in environmental outcomes may take time to be fully realised. In the short to medium term, success will be evidenced by credible progress in reducing releases and controlling pathways, including reduced emissions or mass loads, improved site management, and better control of PFAS sources and waste streams. Over the longer term, success will be demonstrated by stabilisation and recovery of environmental receptors, reduced exposure risks to people and ecosystems, and declining longterm liabilities. A weightofevidence approach, combining early indicators with longterm monitoring, will therefore be applied to confirm durable environmental protection.