By James Arnold BBC News Online business staff

Some people just can't win.

For years, chief financial officers - or finance directors, as they tend to be called in the UK - were derided as colourless bureaucrats.

Now, all that is changing - but not exactly for the better.

Over the past few months, a string of accounting scandals - from Enron to WorldCom, with many others in between - have involved the CFO either as hapless dupe or cunning villain.

Man in the middle

So who are these much-maligned people?

The CFO likes to think of himself - and yes, it is a massively male-dominated job - as a bit of a linchpin.

In a small company, the finance director deals with bankers, manages the payroll, keeps an eye on costs, runs his slide-rule over deals and investments, and organises book-keeping and the annual audit.

The finance director will tend to be the company's de facto number two, and a stint in the finance chair is regarded as useful preparation for the managing director's job.

Bean-counters break out

In bigger, multinational companies, that role becomes dramatically more complex.

Top CFOs have tried to reinvent themselves as the boss's "strategic partner", pulling back from day-to-day counting of beans, and focusing more on how demand and supply of beans may change in the future.

As pressure has mounted to extract shareholder value and keep costs in check, so the strategic role of the CFO has increased in importance.

It might be putting it a little high to talk of "superstar CFOs", but a number of finance directors have emerged from the gloom of the boardroom - most notably Andrew Fastow, formerly of Enron, and Scott Sullivan, formerly of WorldCom.

It was Mr Sullivan, for example, who had the idea of taking over MCI, a much bigger long-distance operator, in 1997.

As Bernie Ebbers, founder and until recently chief executive of WorldCom, said: "It takes a dedicated, astute, and uniquely qualified CFO for an organisation to accomplish what WorldCom has over the past three years."

Too close for comfort

But this neatly symbiotic relationship contains the seeds of danger.

As CFOs have become grander, many have started to pay less and less attention to the tiresome nitty-gritty of book-keeping, allowing all sorts of abuses to go on unnoticed.

Alternatively, a crooked CFO has no-one to watch over him.

As the official ultimately responsible for handing out billions of dollars' of business, CFOs are the focus of frantic attention from bankers and other corporate hangers-on.

And they are particularly cosy with the Big Five accounting companies, from whose ranks almost all senior CFOs are drawn.

Beneath the grey suit...

But the biggest danger of all comes down to simple human ambition.

Throughout corporate history, the finance director was regarded as the managing director or chief executive in waiting, someone serving time in a worthy but dull job until the top seat fell vacant.

But as the CFO's role has expanded, and especially in the very biggest of companies, a new range of pretenders have emerged.

The top of the corporate tree is now populated with presidents, chief operating officers, chief information officers and others, all of whom see themselves at the head of the queue.

... beats a restless heart

Increasingly, multinationals want their CFOs to be pointy-headed financial specialists - accountants or bankers with PhDs in statistics.

And they want their chief executives to be natural leaders, whose job is to look good on TV and keep the markets happy.

That shift has meant that the CFO has lost the natural right of succession, leaving many seething in their well-paid - but not well-paid enough - subordinate roles.

The combination of thwarted ambition, near-unlimited power and the right to sign billion-dollar cheques is a potent one.

It makes bean-counting sound almost exciting.