Forthcoming in Martin Moore & Damian Tambini (eds.) Dealing with Digital Dominance (OUP 2021)This chapter elaborates on challenges and emerging best practices for state regulation of electoral disinformation throughout the electoral cycle. It is based on research for three studies during 2018-20: into election cybersecurity for the Commonwealth (Brown et al. 2020); on the use of Artificial Intelligence (AI) to regulate disinformation for the European Parliament (Marsden & Meyer 2019a; Meyer et al. 2020); and for UNESCO, the United Nations body responsible for education (Kalina et al. 2020). The research covers more than half the world’s nations, and substantially more than half that population, and in 2019 the two largest democratic elections in history: India’s general election and the European Parliamentary elections.