How could so many people be convinced to vote for Donald Trump? Why did so many Brits vote to leave the EU, despite almost unanimous advice from experts, political leaders and celebrities that we should remain? Some attribute these results to the power of Big Data, specifically to the high-tech psychological marketing techniques of a company called Cambridge Analytica. Can the manipulation of data really swing important votes? What are the implications of this approach for privacy and democracy? What does the assumption that a few targeted messages can influence voters’ decisions tell us about elite attitudes towards the electorate? SPEAKERS JAMIE BARTLETT director, Centre for the Analysis of Social Media, Demos; author, The Dark Net and Radicals; presenter, BBC’s The Secrets of Silicon Valley CAROLE CADWALLADR feature writer, Observer SIMON COOKE member, Institute of Direct and Digital Marketing; leader of the Conservative group, Bradford City Council TIMANDRA HARKNESS journalist, writer and broadcaster; presenter, FutureProofing; author, Big Data: does size matter?