Sir Stuart Rose has duly earned his place in history. Marks & Spencer's £1 billion pre-tax profit is its best performance since the days of Sir Richard Greenbury a decade ago.

Forget for a moment the fact that M&S reached the milestone by only £7 million.

The achievement reflects the impressive turnaround in the business over the past four years and makes M&S one of the most profitable companies on the high street.

All has gone very much according to plan, apart from the small matter of a looming recession.

Until the credit crunch came along, Sir Stuart was ready to leave in early 2009. He could then have packed his bags and been hailed as the man who saved one of Britain's best-loved institutions.

Instead, the hard work starts now.

Analysts fear that pre-tax profits at M&S could fall by nearly £200 million this year as it battles cost inflation of 7 per cent and the toughest trading conditions since the early 1990s.

Sir Stuart not only has to steer M&S through nastier economic times. He has to cope with the lingering shareholder anger over his promotion to executive chairman, and he has to help to find a successor.

For all his undoubted ability as a retailer, Sir Stuart has his doubters in the City. He did his best to answer the critics yesterday, insisting that M&S was right to continue its share buyback programme and lower the opening price points on its clothing.

Some worry that M&S is trying to be all things to all people. Attempting to fight John Lewis for the hearts and minds of Middle England while facing up to George at Asda could prove tricky.

In spite of recent difficulties, Sir Stuart still has an extraordinary reputation. We may now get to see how good he really is.

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