Russian interference in the 2016 US presidential election produced the biggest political scandal in a generation, marking the beginning of an ongoing attack on democracy. In the run-up to the 2020 election, Russia was found to have engaged in more “information operations,” a practice that has been increasingly adopted by other countries. In Election Interference, Jens David Ohlin makes the case that these operations violate international law, not as a cyberwar or a violation of sovereignty, but as a profound assault on democratic values protected by the international legal order under the rubric of self-determination. He argues that, in order to confront this new threat to democracy, countries must prohibit outsiders from participating in elections, enhance transparency on social media platforms, and punish domestic actors who solicit foreign interference. This important book should be read by anyone interested in protecting election integrity in our age of social media disinformation.