World-leading sustainable bio-based chemicals and materials (BB-Materials) developed, designed and manufactured in the UK, offer a once-in-a-generation opportunity to transition away from oil-and-gas, creating a resilient-engine for net-zero, and securing and growing hundreds-of-thousands of highly-skilled and productive jobs. Chemicals are in everything we use in our daily lives - food, textiles, energy, batteries, defence products, mobile phones and medicines - ensuring our food security, clothes we wear, heating our homes, affording national security, enabling communications and delivering treatments for diseases. Today, almost all chemicals are made from fossil oil-and-gas, being responsible for ~10% of Global-Greenhouse-Gas-Emissions. The UK chemicals industry has an ambition. By 2050, it will have doubled in size, sourcing 30% of its carbon feedstock from biomass (Innovate UK, 2024, unpublished), with manufacturing of just 15 biochemicals having potential to contribute 5.2 million-tonnes CO2eq GHG-savings and £1.6 billion annually to the UK economy (DESNZ, 2024, unpublished). Through accelerating the commercialisation of BB-Materials, if 30% of chemicals could be bio-based by 2050, this has potential for £26.25 billion annual income. The UK is the home of BB-Materials academic excellence, but other areas of the world are already implementing policies/regulations to drive this sector forwards and the UK is rapidly losing this competitive advantage. Our engagement with 186 individuals and 102 organisations during the Discovery phase concluded that a lack of overarching strategy has led to disconnected departmental policies that hinder BB-Materials commercialisation, and regulations that are better suited to fossil-based incumbents. Due to the nascent nature of the sector, there is limited scientific data and evidence for robust development of regulations, detrimentally impacting the growth trajectory of BB-Materials. Standardised terminology and adequate language for communication is missing, leading to consumer confusion and green-washing. _BB-REG-NET Implementation will establish a network of BB-Material stakeholders, with the aim of developing new tools, standards and approaches to evaluate the quality, performance and environmental and economic impact of BB-Materials, to assess benefit-risk and facilitate sound and transparent regulatory decision-making._ BB-REG-NET will: * Generate evidence using regulatory science tools, such as standards, metrics, peer-reviewed research, to inform policy and assist regulators with complex decisions. * Develop stronger partnerships across the regulatory innovation ecosystem, bringing together different disciplines. * Share knowledge to inform evidence-based policymaking, allowing the sound assessment of risks and benefits of BB-materials. * Provide business-growth opportunities by removing barriers to the commercialisation of BB-materials, which are essential to a UK circular bioeconomy and sustainable economic growth.

**Challenge** The climate emergency is the greatest societal challenge of our time. Chemicals and plastics manufacturing accounts for ~6% of global CO2-equivalent emissions; international aviation, in comparison, is responsible for ~1% (CEFIC-2024). Yet despite movement toward Net Zero, petrochemical production is increasing (IEA-2018). Currently ~88% of chemicals and plastics are made from virgin-fossil resources (Nova-Institute-2023). This fossil-based carbon must be replaced by renewable carbon sources, such as biomass, to manufacture bio-based and biodegradable chemicals and plastics (BB-materials). To remove our reliance on virgin-fossil resources by 2050, we will likely need ~20% of all chemicals and plastics to be manufactured from biomass---yet today, only a fraction are (Nova-Institute-2023). Development of BB-materials is essential to deployment of a UK circular bioeconomy, which holds significant potential for sustainable economic growth, resource efficiency, and environmental conservation (DSIT-2023). Transitioning from fossil-based to BB-materials will require a whole-of-government approach that tackles petrochemical "lock-in" (DOI:10.1016/j.erss.2022.102729). Today, the commercialisation and adoption of BB-materials are hampered by regulatory hurdles, inadequate standardisation, communication barriers, and conflicting policies from different government bodies. BB-materials are not being afforded a level-playing-field with their fossil-based counterparts (Nova-Institute-2024). **Proposal** The Bio-based and Biodegradable Regulatory NETwork (BB-REG-NET) will foster a virtual network of stakeholders from across the sector to address specific challenge areas, including: _**Regulation**_: Current regulations favour fossil-based incumbents, slowing market entry of BB-materials. Legislative hurdles to assess include, REACH, Plastics Packaging Tax, Extended Producer Responsibility Scheme, Simpler Recycling, and waste management and classification. **_Standards, certification, and labelling_**: Standards for Life Cycle Analysis and end-of-life labelling for BB-materials are inadequate and misleading. Labelling schemes and advertising are inconsistent and confusing for consumers. **_Communication_**: Communication about BB-materials is challenging, with terms such as "biodegradable" often being misused, leading to greenwashing. Clear, standardised terminology is needed. **_Policy:_** There is a disconnect between policies across government, hindering commercialisation of BB-materials. Research funding priorities do not align with the Biomass Strategy, DEFRA's simpler recycling guidance, or the EPR scheme. This misalignment perpetuates the unequal footing of BB-materials and reduces benefit to the taxpayer. BB-REG-NET will assess current status and future requirements of the sector, and develop evidence-based tools, standards and interventions to support formulation of policies that accelerate growth of innovative BB-materials, reducing our reliance on fossil resources.