Some firms, such as Best Buy, an electronics retailer, recognise this and try hard to evaluate staff solely on performance.

ECONOMIST: People who work from home are less likely to be promoted

In March Compass won a contract with Philips, a Dutch electronics group, to feed, eventually, all 265, 000 staff in 60 countries.

ECONOMIST: Contract catering

Vanguard's supermarket in Shenzhen has 350 staff, and 500 other people promoting not just expensive electronics, but also cheap items like toothpaste and shampoo.

ECONOMIST: Retailing in China