Background The presence of the invasive alien grey squirrel (Sciurus carolinensis) in the UK is detrimental to several native species and the overall health and resilience of affected woodland ecosystems. The native Eurasian red squirrel (Sciurus vulgaris) is particularly threatened by grey squirrels, but to date there has been no clear pan to stem its population growth. A collaborative management framework that crosses administrative boundaries is required. Currently, the approach to grey squirrel management lacks coordination, focus and adequate funding. Anglesey is a 720 km2 island in North Wales from which grey squirrels have recently been eradicated. Objectives The SciuriousLIFE project aims to: Develop mechanisms to prevent the unintentional introduction of grey squirrels to currently uncolonised woodland landscapes; Develop early warning/rapid response mechanisms to ensure Anglesey is not recolonised; Develop rapid response mechanisms to mitigate the impacts of grey squirrels in urban woodlands with high biodiversity and tourism value; and Develop early warning systems to detect grey squirrels in sparsely populated rural landscapes; Develop more efficient strategic mechanisms to evolve community-based grey squirrel management; Quantify the financial and community-based resources needed to achieve regional eradication; Share knowledge gained across the EU; Use knowledge exchange and trust building processes to aid the development of a broader IAS management; Test the impact of measures to increase public awareness and community capacity associated with grey squirrel management; and Inform the development of a long-term management framework for grey squirrels in the UK. Expected results: Prevention of Anglesey recolonisation; Preventing grey squirrel colonisation of the largest network of grey squirrel-free woodlands on the English mainland; An early warning system to prevent grey squirrel reinvasion in a 165 km2 section of County Gwynedd in north Wales, following grey squirrel eradication from 1 500 hectares of woodland habitat; An early warning system developed to protect the largest network of grey squirrel-free woodlands on the English mainland; Eradication of grey squirrels from 1500 hectares of woodland habitat within 165 km2 of the county of Gwynedd; Eradication of IAS grey squirrels from a specific Northern Irish landscape unit through direct grey squirrel control and creation of a community-based early warning and rapid response network; New urban IAS management communities in north Merseyside created to improve the sustainability of protection measures for Sefton coast woodlands; New grey squirrel management by 50 private landowners across Northern Ireland; Seven existing Northern Irish squirrel community groups supported to increase their membership by 10% from a January 2016 baseline; Creation of three new grey squirrel management groups in Northern Ireland; Four annual knowledge fairs held; Three best practice guides published; Four academic papers published in peer-reviewed journals; and Increased public understanding of grey squirrel management.