Context The National Biosurveillance Network (NBN) is a government initiative supported by the Cabinet Office and brought about by the re-evaluation of the biosecurity risk landscape, which considers the evolving priorities since Covid-19 and rapid advances in science and technology. In 2023, the UK government updated its biological security strategy [@366811] and a significant objective of this is to develop a network that enables effective detection of biological risks and subsequently respond to them. The NBN is a direct response to this need. While investment in biosecurity, science and technology remains high across government departments, there are challenges to building a connected network around these programmes that enables the fast detection of threats in our environment as and when they occur. UKHSA wants to understand the picture across government, where the gaps are and how to fill them to create a coherent network delivering functional biosurveillance [@366836]. Highlighted in the UK biological security strategy, the NBN shares priorities with the PATH-SAFE programme, as both aim to establish cross-governmental action to tackle threats to public health, and specifically threats of a biological nature. The NBN aims to assess biosecurity programmes across government, of which PATH-SAFE is one such programme of relevance. One similarity between the programmes is that they span all four nations of the UK and endeavour to enable and address challenges to cross-governmental action. While the NBN focuses on a much broader scope of bio surveillance than PATH-SAFE does, there are opportunities for learning on data sharing across government bodies, technical expertise to identify threats, and strategies to mitigate these threats and contribute to the development of a UK-wide solution to biosecurity threats. Influencing in action The NBN aims to build a connected, cross-government, cross-industry, cross-UK network to ensure threats are detected and responded to more effectively. The PATH-SAFE team have been able to contribute to this aim by inputting into the NBN at strategic points, from the discovery to alpha phase. This has primarily been through participation in discussions as part of the NBN’s programme of activities, as well as separate and specific conversations around programme learnings and sharing of materials, as many of the PATH-SAFE technical outputs are relevant to what the NBN aims to assess and identify.a The PATH-SAFE programme has also helped support the NBN by providing operational insights, sharing learning and helping the NBN understand how to work with HMT and SOF financing. Enablers of influencing the NBN The UK Biological Security strategy [@366811] has set out a top-down mandate for working, collaborating and sharing learnings, which has been an enabler for the PATH-SAFE programme to influence and support the NBN in a strategic manner. This has also been complemented by the bottom-up approaches led by key individuals across FSA, UKHSA and the Cabinet Office, creating a shared space for cross-government collaboration and learning at an operational level. Evidence suggests that professional relationships between various government organisations have been a major enabler of influence, as have opportunities to network enabled by conferences that actively engage stakeholders working in this space and across government, subsequently strengthening buy-in from individuals within the various organisations.b Challenges in influencing the NBN Challenges to further enhancing support for the NBN are mainly structural and derive from circumstances such as the two programmes being at different stages of development. The PATH-SAFE programme began in 2020 and is due to end in 2024, while the NBN is still in early stages of development. This may pose challenges to real time-shared learning – although lessons from PATH-SAFE would still be useful to inform NBN operationalisation. Another key challenge relates to people and funding. For successful collaboration across these programmes and its various organisations, resources will need to be made available to encourage collaboration and discourage siloed working. Due to the evolving nature of the programme, as well as limited resources and potential staff turnover experienced in government departments, this poses a challenge to enabling effective influence and support. Learning for the wider programme and surveillance sector The NBN is ongoing and in the early stages of its development, while the PATH-SAFE programme is in its final stages, with some of its outputs still being developed. Nevertheless, there is significant opportunity to incorporate lessons learned from the PATH-SAFE programme into the NBN’s programme of work. Communication across government, trying to break out of silos, and connecting people and data, are of major importance and a significant determinant of the success of both programmes. A combination of top-down and bottom-up efforts can be effective – indicating that government buy-in and individual engagement are both crucial factors in determining success. Early engagement is helpful: given the NBN has not yet been operationalised, this represents an effective opportunity for input and influence. These insights can also be applied to other areas of the PATH-SAFE programme to ensure that learning from the workstreams and projects feed into any new workstreams or additions that develop, and directly counteract siloed working and other challenges to shared learning. Insights gleaned on data infrastructure, data requirements and data sharing will be particularly critical to enabling NBN to effectively navigate potential challenges that may emerge.