Development plays a major role in stopping biodiversity loss. But the ‘silo species’ protection of legislation (where certain species are protected while many are not) means that development can be legally compliant yet cause biodiversity loss. Biodiversity Net Gain (BNG) policies can help overcome this by requiring that development causes no overall loss of biodiversity and brings a benefit. However, offsetting biodiversity losses in one location with gains elsewhere is controversial because people suspect it to be an easy way for developers to buy their way out of conservation requirements. Yet the good practice principles (GPP) of offsetting provide several advantages over existing legislation for protecting biodiversity from development. This presentation describes the learning from implementing BNG approaches based on GPP. It regards major upgrades of the UK’s transport networks, which involved removing vegetation in order to construct and safely operate new infrastructure. While low-lying habitats were retained, habitats disrupting the running or safety of transport networks could not. Consequently, achieving BNG within the transport corridor was not possible and offsetting was required. The first lessons learnt were on obtaining commitment from business leaders to go beyond legislative requirements and deliver BNG, and on the institutional change necessary to embed GPP within daily operations. These issues were addressed by overcoming the challenges that biodiversity poses for business including: biodiversity cannot be measured easily unlike other sustainability factors (e.g. carbon, water) that have metrics for target-setting and measuring progress; and, the mindset that biodiversity costs money and does not generate cash in return, which is the opposite of carbon for example, where people can see how sustainability actions save money. Challenges were overcome by presenting the GPP as a cost-efficient solution to critical risks facing the business that also boosted reputation, and by using government-issued BNG metrics to develop toolkits charting BNG progress whilst ensuring that BNG decision-making was based on rich ecological data. Institutional change was best achieved by supporting, mentoring and training sustainability/environmental managers for these ‘frontline’ staff to embed GPP within the business. The second learning was from business partnerships with local wildlife groups where development supported their priorities for nature conservation, and where these groups had a say in decisions about achieving BNG. This inclusive approach enabled multi-sector collaborations to manage trade-offs between achieving BNG locally to the development whilst contributing towards national conservation priorities. But key was strengthening linkages between biodiversity measures implemented for development and conservation work undertaken by local organizations so that developers support BNG initiatives that really count.