By Nicola Seare
BBC Money Programme
Marks & Spencer's new chief executive, Stuart Rose, has one of the toughest jobs in retailing.
M&S' position on the High Street is under threat
The High Street giant is facing one of its most challenging phases in its 120 year history.
Despite over 10 million customers a week, M&S have not recaptured the glory days 1997 and1998 when it made over £1bn in pretax profits.
Market growth has stalled and M&S recently announced that total sales have slipped; sales in the 10 weeks to 18 September were down 6.3% compared with the 10 weeks to 13 September last year in shops that were open both years.
"It's not going bust and it doesn't have outrageous debts but it's in a cycle of decline and it's hard to see where that's going to stop," BBC Business Editor Jeff Randall told the Money Programme.
"That's the task that's facing Stuart Rose, to stop that cycle of decline turning in to a complete rout," he said.
Not only has Mr Rose got a mammoth task ahead of him, he also has retail billionaire Philip Green breathing down his neck.
Back in the summer, Mr Green's potential takeover offer for M&S turned into one of the most extraordinary and dramatic business battles of the last few years.
From the moment Mr Green's ambitious plans were first revealed during spring, the M&S board was thrown into turmoil and there was a management shake up which led to the ousting of the incumbent chief executive and chairman and led to the appointment of Mr Rose.
What ensued was a highly charged summer for both Mr Green and Mr Rose.
In June, bemused M&S employees witnessed an altercation between their new chief and his former friend Mr Green outside their Baker Street head quarters.
The reason for the argument became clear when it was revealed that Mr Green had earlier approached Mr Rose to take a role in his acquisition vehicle for M&S.
Mr Rose managed to stave off three potential offers by the billionaire before Mr Green finally threw in the towel in mid July.
Although Mr Green did not come away as the new owner of M&S, he had managed to raise an estimated £9bn to buy the chain of stores, the largest sum of money ever raised in Europe by a private individual.
The key to turning M&S's fortunes around is women's wear.
Subsequently, Mr Green has declared high street war against M&S using his Bhs stores and his Arcadia group, which include the fashion stores Dorothy Perkins and Top Shop.
When interviewed by the Money Programme, Mr Green said: "They've got the headache, we've still got the money, lets see if they're any good."
"The one thing you don't get in this business is time," he said.
"You don't suddenly say - do me a favour, can you not open your shops for 6 months while I catch up."
Richard Hyman of retail consultancy Verdict Retail stressed how important it is to get this area right.
Will Mr Green have the last laugh?
"Women's wear drives the foot fall, women's wear is why most of the 10 million people go into the stores every week," he said.
"If they get that right, everything else has got a good chance of success."
Mr Rose has always maintained that his vision for M&S will begin to show fruition next year when he has had a chance to implement his changes.
However, Scott Moeller, takeover expert from Cass Business School, points out that City investors may not be that patient to see results.
"The City is not an easy judge," he said.
"With a retail firm, they look at weekly results and certainly monthly results to see what in fact is taking place.
"Stuart Rose doesn't have the luxury of time in order to deliver what he has promised back in July."
And in the new year Green could potentially come back and make another bid for Marks and Spencer.
The Battle for Marks and Spencer was broadcast on BBC Two on Wednesday 6 October at 1930.