'It's about the money, pure and simple'

Simon Renton, a history lecturer at University College London, loves his job.

He said: "As far as job satisfaction goes, it doesn't get any better than this."

The fact, then, that the 52-year-old is contemplating uprooting his family and moving to a new job 3,500 miles away in the US appears bizarre. "It's money, pure and simple. I'm applying for three jobs, which I'm led to believe I have a good chance of getting, because I'm being offered at least a 50 per cent pay rise."

Mr Renton, married with a child, has been at UCL for nearly 13 years. He earns £28,000. His specialist area, the history of crime, is highly in demand by universities in the US, where penal policy is an intensely debated issue.