When I first served on the boards of public companies, 20 years ago, leaks of confidential information were rare. But now it seems almost everyone is willing to spill the beans. And it means running a business with a public profile is harder than ever.

Why does this happen? Some people just cannot keep secrets: they get a kick from revealing something hush-hush – even if it damages the business they serve. Certain directors are congenital gossips, and too immature to serve on the boards of serious organisations. In my experience, you generally know the leaker, but proving it can be nearly impossible. Others have an agenda: they gain favours from journalists or get paid for passing on a tip-off, or perhaps they win some office skirmish thanks to their revelations. And of course companies leak as deliberate policy, pre-empting formal announcements as a matter of course.