Today's finance director is a wearer of many hats. Besides having a knack for figures and a grasp of the way the organisation is run, he or she must be a risk manager, a planning expert, an IT guru, a guardian of corporate governance and above all, a consummate strategist.

So it's no surprise, given the privileged overview that a finance director has of their organisation and the many transferable skills they share with their boss, that an FD is often given the nod when the chief executive's chair falls vacant.

Peter Clarke, of hedge fund company Man Group, and Nationwide's Graham Beale are two examples of finance directors who have been promoted to chief executive this autumn and the trend is not new.

According to Accountancy's latest survey of FTSE 100 accountant chief executives (see p36), the fashion for finance directors-turned-chief executives shows no sign of abating. While the overall number of FTSE 100 chief executives who are trained accountants has dipped from last year (there are now 20, compared with 24), accountancy still provides more chief executives than any other single profession including banking, engineering and law.

These findings come as no surprise to CIMA chief executive Charles Tilley, who was himself formerly finance director of investment banks Granville Baird and Hambros. 'I definitely think finance directors make good chief executives,' he says. 'The driver of increasing shareholder value is the finance director. They will manage the planning process and the performance management process. They speak the language of business finance and are in a good position to move up to being chief executive.'

But while it is undoubtedly important for a chief executive to be financially literate, there are other qualities that he or she must possess to succeed, foremost of which is leadership.

Most finance directors will have leadership skills to a greater or lesser extent. A FTSE FD is likely to manage a finance team that is 50 to 200 people strong, while the FD of a smaller organisation will head a more compact unit. But there is a big difference between leading a group of fairly like-minded people and managing thousands of staff from a variety of backgrounds, as ICAEW chief executive Eric Anstee found out.

'When you run a FTSE company you get people from all walks of life and they each bring different issues,' says Anstee, who acted as group FD and deputy chief executive of Eastern Electricity in the 90s and later as FD and chief executive of FTSE 100 financial services group Old Mutual.

'I was involved in putting through major cultural changes at Eastern and I was dealing with everyone in the workforce, from the top to the bottom.'

Anstee believes that besides financial nous, FDs need marketing and sales skills as well as HR and softer skills if they are to make good chief executives. He adds that chief executives who come from a sales and marketing background need to understand more about internal controls to succeed in the top job. 'Both disciplines need to come to a broader understanding,' he explains.

Simon Carruth, who became chief executive of human rights charity the Medical Foundation for the Care of Victims of Torture in February, after serving as its finance director, says communication skills are vital in his role. 'The job of communication is quite demanding because of the expectation of staff to have full involvement. Everyone is keen to make their voices heard.'

Another important consideration for FDs who are would-be chief executives is whether they are willing - and able - to change their mindset. As custodians of their organisation, FDs must be cost and risk aware. But as chief executives, they should be thinking about how they can grow their business and look forward. As a result of this, they need to take risks.

Anstee believes this is when an accountancy qualification comes into its own. 'Our basic training gives us a phenomenal grounding in all aspects of business,' he says. 'You're not just looking at the numbers. Your chartered accountancy qualification gives you what you need to take over and run a business.'

Richard Sexton, head of assurance at PricewaterhouseCoopers, suggests that finance directors' familiarity with risk can actually give them the edge as chief executive. 'In order to take risks effectively, you have to know that you're taking a risk,' he argues. 'People who observe risk are in a good place to take an entrepreneurial step. The boldness of taking an entrepreneurial step doesn't relate to the job you're in but to your personal skills.'

FDs are sometimes dismissed as potential chief executive material due to the primary inward-looking nature of their role and their perceived focus on the 'detail' as opposed to the 'big picture'. But Sexton disputes this. 'You have to be able to cope with detail and overview in any senior position,' he says. 'Any good executive has to know when to intervene and when to let people get on with it.'

But not everyone is convinced that the finance director is almost by definition the chief executive-designate. John Collier, a senior financial recruitment specialist with Clive & Stokes International and former secretary-general of the ICAEW, believes that finance directors are actually better suited to the role of chairman. 'The skills that a finance director has - probity, presenting reliable information in a balanced way and responding to people who challenge that, and persuading the board to stay in touch with reality - these are important skills for a chairman,' he says. 'The chief executive picks up on the information, finds a way and leads the team. I'm not sure the classic finance director or chartered accountant training means they are particularly good in the chief executive role.'

An exception, he suggests, is the financial services sector where an increased emphasis on regulation and compliance means a finance director may be the most suitable person to fill the chief executive's shoes. This is borne out by Accountancy's survey, which reveals that seven of the 20 accountants who are FTSE 100 chief executives work in a finance-related field. He also thinks that where a company is looking to make acquisitions or holds a portfolio of different operating companies, the transactional and analytical skills of the finance director-turned-chief executive come into their own.

CIMA's Charles Tilley believes that whether a finance director will make a good chief executive depends on both the company and the person. 'If the company needs to focus on maximising brands, maybe the CEO needs to be a brand expert,' he says. 'If the company is about reversing its financial position, maybe a finance director is the right person. It depends on whether the company is in growth mode or turnaround mode.'

Collier argues that those FDs who do eventually bag the top job have usually spent time at the coal face, away from the narrow finance function.

'If FDs haven't been in a customer-facing role during their career, it is a disadvantage. Most of the finance directors who become successful chief executives that I see have had a customer-facing role,' he says.

But even if a finance director has the right skills to succeed the chief executive, they might still question whether it's a role they actually want.

'People talk about the loneliness of the chief executive's job and I think that can be true,' says Anstee. 'It's up to the chief executive to find ways to deal with it.'

There is nothing more frustrating for an ambitious professional who wants to climb to the top of their field than being forced to wait on the sidelines. Just ask Gordon Brown.

The chancellor's public spat with prime minister Tony Blair hogged headlines in September when junior defence minister Tom Watson and six parliamentary private secretaries resigned after they signed a letter urging Blair to quit.

It is no secret that Brown has longed to hold the reins of UK plc ever since Labour came to power in 1997. Rumour has it that the two men reached an agreement in 1994, when Brown agreed not to run against Blair in the leadership contest that followed John Smith's death provided Blair agreed to step down after a specified period of time and hand the job over to Brown.

Now that Blair has announced his intention to stand down during the next 12 months, it seems Brown is closing in on the premiership.

But first he must win a leadership election and to do that he needs to convince the Labour Party of his credentials. A straightforward business, you might think, given his robust performance as chancellor. But nomination committees are an unpredictable bunch and there are those who question whether the stern Scot has the leadership and communication skills, not to mention the charisma, to pull it off. He might have an impressive CV but critics say Brown is better suited to the intellectual rigour and detailed work of the Treasury rather than the diplomatic and political juggling act that being the public face of the country requires.

The Man Group's Peter Clarke is the best paid finance director in the FTSE 100, but he can look forward to even fatter pay cheques when he takes over from outgoing chief executive Stanley Fink who earned nearly £6m this year. Clarke's background in investment banking, together with six years as Man's FD under his belt, makes him the seemingly perfect candidate to lead the thriving hedge fund company.

Graham Beale has been with Nationwide since 1985, working his way through a variety of finance functions until he made FD. From April he becomes the building society's chief executive, when he will oversee probably the biggest transaction of his life provided Nationwide's merger with the Portman building society goes ahead.

Julian Roberts is chief executive of investment company Skandia, whose principal shareholder happens to be Old Mutual, the group where he was formerly finance director. Roberts has a solid background in the financial services sector, having also held senior roles at Sun Life & Provincial Holdings and Aon.

A rising star at media company Pearson where she was finance director for four years, Rona Fairhead is credited with having the financial acumen and business nous to revive the fortunes of the ailing Financial Times Group. She was installed as the group's chief executive in the summer, charged with turning an under-performer into a high achiever.

When Charles Allen stood down as chief executive of ITV in August, the television channel was feeling the crunch of low viewing figures and falling advertising revenue. Although he was widely admired for his good 'business brain', some in the media community questioned whether the former British Steel accountant had the creative flair to lead ITV in the digital era.

Having said that, his leadership has been somewhat vindicated by the difficulties ITV has had in its search for a suitable successor.

Friends Provident FD Philip Moore becomes the company's chief executive in January 2007 when he takes over from outgoing CEO Keith Satchell. Moore is something of an insurance guru, having previously been corporate director of finance and head of mergers and acquisitions at AMP (UK) and the partner responsible for PwC's East Asia insurance consultancy practice.

J Sainsbury chairman Philip Hampton has been finance director of a string of blue-chip companies including Lloyds TSB, BT, BG Group and British Steel.

ICAEW council member and former Baker Tilly chairman Clive Parritt is now non-executive chairman of troubled online gambling company BetonSports.

CIMA fellow David Kappler joined the board of Premier Foods after serving as finance director of Cadbury Schweppes for nine years.