The COVID-19 pandemic has presented some significant challenges to the nuclear industry, complicating operations and the delivery of both safety and security. This paper seeks to explore the response of the UK Civil Nuclear Sector , focusing on nuclear security. It considers potential disconnects between the national and operational levels, as well as exploring in detail the response of the nuclear industry. Drawing on in-depth interviews with key stakeholders in UK government, the regulatory body, a range of nuclear duty holders and the national armed response capability, the paper identifies a number of common challenges and discusses how these were overcome. These include absenteeism, the sharing of security sensitive information, physical protection system testing, supply chain management and the remote monitoring of staff. In addition, broader lessons learnt that may serve to shape the future delivery of nuclear security are extracted, for example, a greater remote component of regulatory assessments, supported by increased data collection.