When the Berlin Wall fell in 1989, East Germany's ministry for state security is said to have had a representative for every seven citizens (the Gestapo had one per 2,000, the KGB one per 5,830). The Stasi knew everything, from your reading habits to who you drank with. It tapped phone lines, traced citizens using radioactive material, and even collected smell samples from people's underpants. As the state's paranoia was cranked up, even innocuous acts became grounds for suspicion. The logic was: 'We're monitoring you, so you must be guilty of something.' But the drive for total control had the organisation creaking under its own weight: laid end-to-end, its exhaustive files would stretch 180km. In this culture of suspicion, colleagues, friends and family were turning each other in. With tools such as e-mail, you don't need armies of informers and acres of files to know what your staff are up to. But it's best to let them get on with it. Build a culture of trust, not a wall between you and your team.