This Practice Note summarises the evolving policy and regulatory position in respect of the potential future deployment of Advanced Nuclear Technologies and, in particular, small modular nuclear reactors (SMRs) in the UK. Details of, and links to, key policy documents are included in the Practice Note, together with an overview of the position relating to ANT licensing, planning, siting, decommissioning and insurance. For further practical guidance on the financing of energy, power and resources projects across a number of sectors, including those discussed in this Practice Note, see also textbook: Energy and Resources Financing: A Practical Handbook. What are Advanced Nuclear Technologies (ANT)? The term ‘ANT’ is used to aggregate the most recent types of nuclear technologies. These are 'small modular reactors' (or SMRs), 'small and medium-sized reactors', micro nuclear reactors and advanced modular reactors. The term 'SMR' is used interchangeably to mean 'small modular reactors' or 'small and medium-sized reactors'. Both are advanced smaller-scale nuclear reactors. According to the International Atomic Energy Agency (IAEA), small-sized