The moral dimension of data is typically associated with privacy, and the fear of misuse or accidental disclosure. But in an age of big data, this thinking is archaic and backwards. Big data techniques are now so powerful that data-scientists and businesses actually have a moral imperative to apply data to solve the world’s challenges – not to use big data would create greater harm. In areas as diverse as healthcare and humanitarian crises, over-bearing rules block the benefits. Instead, we need a sensible balance in favour of harnessing big data to improve the world.