Do I know him?
Possibly. He's in the news as the man who has just signed off on his company's $8.5bn deal to sell a majority stake in its Indian oil business to the mining giant Vedanta. But you might just as well remember him as a Scottish rugby international – he played for the Bravehearts five times on the wing – or the man to whom George Bush and Tony Blair turned to check each other out.
Bush and Blair, really?
Absolutely. Sir Bill was a pupil at Fettes College, the Edinburgh private school, with our former prime minister, you see (in fact, they were leading lights of the debating society). And because his father had invested in the Bush family oil company back in the Fifties, when Sir Bill wanted to learn about the business in the Eighties, the Bushes were his first port of call. He and George W Bush became firm friends. Naturally, once Messrs Blair and Bush began dreaming of high office, they asked about each other via Sir Bill.
A man of influence, then?
It would seem so, but not just in the political sphere. Sir Bill really has built Cairn into an impressive operation. He founded the business in 1981 once his rugby career came to an end and has built it into Britain's fourth-largest oil and gas company. Yesterday's deal should enable it to hand shareholders a chunky special dividend and provide it with all the cash it needs to pay for ongoing exploration in Greenland.
Is another big score likely?
Well, not much is going to beat scoring four tries for Scotland on his debut against Japan. But having already struck oil several times, most noticeably in Rajasthan, India, Sir Bill has high hopes for Greenland. Satellite pictures appear to show shimmering in the waters around the coast of Greenland, which could be oil oozing out of the sea bed.
Still, this is a risky business?
You're not joking. Sir Bill's political connections might come in useful for Cairn's bid for work in Iraq, but this is scary stuff. So too is the project in Nepal where Maoist rebels have caused a few difficulties.