Big data is changing economics and the way causal relationships are studied. In this video, Christian Hansen and Soumaya Keynes discuss the importance of big data for econometrics. Big data offers a lot of information and it is easier to draw policy lessons. It also gives more flexibility without forcing researchers to impose control variables, allowing more reliable conclusions to be obtained. This video was recorded in March 2016 during the Royal Economic Society’s Annual Conference held at the University of Sussex.