There is growing UK and international interest in using ‘small modular nuclear reactors’ (SMRs) to generate electricity, and the UK Government announced a number of measures to support SMR development in the 2018 Nuclear Sector Deal. Stakeholders suggest that, compared with conventional nuclear reactors, SMRs could offer cost savings to operators and consumers, more flexible energy production and a greater choice of potential sites. This note examines key aspects of SMR technology, their economics and regulation.