Is that a bug under your boardroom table?

The news that Michael Howard, the former leader of the Conservative party, is to become the European chairman of Diligence, a US-based corporate intelligence company, is the latest sign of gentrification in a sector that was once seen as the preserve of shifty types who rifle through bins under cover of darkness.

There is still a role for that sort of operator, but as the commercial investigation game gets serious, a growing number of private investigators have a background in investment banking or the law. Indeed, one security industry analyst, Equitable Services, has predicted that the global private security market could be worth £150 billion by 2010, fuelled by mushrooming demand for high-quality commercial intelligence.

As more and more billionaires emerge from the Middle East and Eastern Europe, for example, there is a corresponding need for forensic analysis of the source and stability of their wealth. And companies such as Kroll Associates, Control Risks, Risk Advisory, GPW and even Pinkertons, the venerable American private detective agency, are prospering as never before.