In two new research briefings, Africa Check, Chequeado and Full Fact have teamed together to explore two major issues for fact checkers around the world - conspiracy theories, and communicating uncertainty. Conspiracy theories: who, how, what next? A conspiracy theory is not simply an alternative explanation of events, waiting for evidence to prove (or disprove) it. Conspiracy theories can cause serious harm when beliefs turn into behaviours, such as when vaccine hesitancy results in lower immunisation rates, or false claims about the 5G network leads to arson. When it comes to solutions, research is just beginning to emerge, and mostly from an Anglo-American angle – though scholars have reflected on the role of conspiracy theories in history since the 1950s.