Small Modular Reactors (SMRs) are gaining recognition among policymakers and industry players as a promising nuclear technology. SMRs can be defined as nuclear reactors with a power output between 10 MWe and 300 MWe that incorporate by design higher modularisation, standardisation and factory-based construction levels enabling more predictable delivery models based on the economies of series. Today, more than 50 concepts are under development covering a wide range of technology approaches and maturity levels. The value proposition of the SMR technology also includes potential financing and system integration benefits. These attractive features, however, rely on a business case that requires the development of a global SMR market to become economically viable. Large-scale deployment of SMRs faces several technical, economic, regulatory and supply chain challenges and will need considerable governmental efforts and efficient international collaborative frameworks to be realised in the next decade.