Whistleblowing has a long history. The Ancient Greeks had a term for it: parrhēsia, or fearless speech. In the seventh century, a British king introduced the world’s first whistleblowing law, encouraging his citizens to report those who worked on the Sabbath. Ever since the phrase ‘whistleblower’ was coined in the 1970s, the concept has gained renewed salience. In an era of widespread fraud and corruption, those prepared to speak up perform an essential service to society.