A decade of excellence? The heroes and zeros

For all the gloom of the past two years, the first decade of the 21st-century has produced some phenomenal success stories. James Moore picks the 10 best business leaders of our time

Bob Diamond

In 1986 Margaret Thatcher unleashed her "big bang" on the City in the hope that sweeping away the regulation she believed had stifled Britain's financial centre would facilitate the creation of genuinely world-class British investment banks.

But only now have we come close to realising her ambition, thanks to Barclays' (not so) quiet American. From the ashes of BZW, he turned the debt specialist Barclays Capital into a force to be reckoned with, making it the bank's most profitable division. Losing out to John Varley in the race to replace Matt Barrett as chief executive, his part of the business went from strength to strength. Reportedly never that keen on the planned all-share merger with ABN Amro (a lucky escape) his master stroke was finding a much better deal, taking over the US assets of the bankrupt Lehman Brothers with none of the liabilities. It is a move that has vaulted Barclays (which survived the credit crunch without a government bailout) into the investment banking Premier League.

Larry Page, Sergey Brin

Some detractors begrudgingly call it the world's largest online advertising sales company, yet Google is a company of big ideas, and its founders consistently look to innovate. It dominates in the staggering task of indexing the nebulous entity that is the internet, and has set about offering free access to the world's literature (Google Books), videos (YouTube) and well, the earth. Who hasn't found their house on Google Earth or looked down their street on Google Streetview? Eric Schmidt might be the chairman and CEO but it is Page and Brin who built this iconic business and both continue to play key roles in its success. How many business people can claim to have created a brand new verb? Despite all attempts to rival it, Google is just better. Some of the issues that now confront the company have led some to question whether it truly lives up to its motto "do no harm" today. But its success is undeniable.

Sergio Marchionne

Not long ago, Fiat seemed destined for the great scrapheap in the sky: uncompetitive products, high cost production, a loveless marriage with General Motors, and overly reliant on a stagnant home market. Rudderless, Fiat needed fresh leadership. It got it, from Sergio Marchionne, in 2004. He forced GM to cough up $2bn to end their partnership, which helped fund appealing new cars, especially the cutesey Fiat 500, and boosted the firm's presence in fast growing markets such as Brazil and eastern Europe. Fiat Auto is back in profit and its last act of the decade is to buy into Zastava of Serbia, another low-cost production base. But is Fiat's acquisition of Chrysler a step too far? Marchionne sees the potential fit: Fiat good at small cars, the Americans at larger ones and SUVs. Critics point out that no transatlantic auto merger has ever worked.

Michael O'Leary

In the eyes of many, O'Leary will be seen as by far the most annoying member of the top 10, beating even Simon Cowell. But you can't argue with his success or his chutzpah. Aggressive, often obnoxious, but also undeniably charismatic, he ran rings around the Panorama team despatched to expose him and his business practices this year just as he's been running rings around his competitors. Love him or hate him, you just can't ignore him, or his manifest skill at turning ever potential brickbat to his advantage. How long people will put up with Ryanair's occasionally lacklustre service and all those extra charges for bags, children, even (potentially) using the toilet on flights remain to be seen. But O'Leary also has an army of fans who have learned to work the Ryanair system to take full advantage of his rock bottom fairs. And competitors, while he makes them gnash their teeth, are increasingly copying his methods.

Warren Buffett

While there may have been a few bumps in the road during the credit crunch, it is impossible to argue with Buffett's long term performance. The "Sage of Omaha" is either the richest or the second richest man in the world (depending on whose list you care to be reading and how his portfolio has performed) and has done it by resolutely sticking to his "value investing" philosophy. That meant he started the decade looking very clever – he didn't get involved in the madness of the tech boom because he said he didn't understand it (and perhaps because most didn't make any money). And while the recent recession has had more of an impact, no one would bet against him coming good in the end and enjoying another decade at the top. Above all, however, what we like best about Buffett is the never-ending string of witty aphorisms that pepper his letters to shareholders and his speeches at the annual convention he holds for investors in downtown Omaha (more popular than Star Trek festivals these days). "It is only when the tide goes out that you find out who has been swimming with no trunks," he once told us. And during a two-year credit crunch, how right the great man was proved.

Simon Cowell

To those who enjoy music, Cowell could easily find himself among the villains. But, in business terms, that's a testament to the phenomenal success of the man and his multifarious formats. With X Factor, Cowell has probably done more to rescue ITV than its new chairman Archie Norman will ever do. He's also a Brit who has managed to make a huge success of the US market (no mean feat). He's not a man for the boardroom, he doesn't wear a suit, he's never run a quoted company nor will he. But Cowell has proved himself an entrepreneur of the top rank. Truly a businessman for the times.

Jeff Bezos

Astonishing that Amazon was once something of a joke, lampooned in The Simpsons and elsewhere during the dot.com implosion as the decade got underway. It is Bezos who has had the last laugh. Just as Tesco has expanded beyond groceries, Amazon is now way more than just an online bookseller, selling everything from watches to clothing to MP3s (offering a serious threat to iTunes). And if you can't get it from Amazon itself, it is almost certain someone else will be selling it on the site, now the company has followed eBay's lead by becoming a "portal" used by other traders. Then there's the Kindle e-reader, which may yet do for reading what iPods have done for music. There are more competitors now and there may be "issues" with staff relations. But Bezos has been hugely influential in changing the way we shop and he's not done yet.

Sir Terry Leahy

What makes Sir Terry stand out from a crowded field, beating rivals such as Sir Stuart Rose and Sir Philip Green? There is the longevity and sustained success, but what gives Sir Terry an edge is the way Tesco's international operations have taken off. Exporting British formats has been the death of many an ambitious retail boss. Sir Terry has made it work; overseas floor space now exceeds that in Britain. Back home Sir Terry's Clubcard loyalty card concept provides priceless customer intelligence that has helped the company keep ahead in a brutal market. Then there's the relentless push into new areas such as banking. Perhaps it's because the boss still visits at least one store a week. Perhaps he's just better. Every little helps.

Sir John Rose

Sir John Rose took the helm at Rolls-Royce in 1996, and has made the company the roaring success of UK manufacturing. He oversaw an acquisition spree and sealed a string of mega-deals from the Boeing 787 to the Ministry of Defence's Hercules transporter to the Eurofighter Typhoon. But most significantly of all, Sir John has shifted Rolls-Royce's focus. The company is Britain's biggest exporter, a giant of turbine engines and propulsion systems with a keen eye on Britain's much-vaunted nuclear renaissance. But more than half of its revenues come from servicing the engines it has sold. Rolls-Royce is also positioning itself as a bulwark of the UK's knowledge economy. Sir John has been a visionary at a transitional time for industry, and he has taken Rolls-Royce with him.

Steve Jobs

If anyone has come to epitomise Silicon Valley it is Steve Jobs. His Apple has not just made products. It has, with the iPod, created a cultural icon that has changed the way we listen to music. Then there's the iPhone, rapidly on the way to attaining iconic status too, not to mention the multitude of Macs, whose operating system is rated by geeks as far superior to anything Microsoft has come up with. And they all just look so, well, good, combining elegance with unbeatable functionality. Jobs has survived scrapes with the authorities (over share options in 2001) and severe illness (he's survived cancer and a liver transplant – how many CEO's can say their livers move share prices) to stand at the head of a company that is at the height of its powers. Egotistical, demanding, but occasionally inspired, Jobs seems to move effortlessly between the grey world of big business and the star-studded celebrity scene. Staying at the top in technology is no mean feat, requiring continuous innovation. And yet no one would bet against Jobs being on this list in 10 years' time.

The villains: A decade of greed

And now for the villains. This list highlights the dark side of business. Top of the list must be Bernie Madoff. The one time pillar of Wall Street respectability whose funds the great and the good flocked to back was no more than a cheap conman with a pyramid scheme. His wasn't even an innovative fraud.

It's supposed to be bad form to speak ill of the dead, but most people would make an exception for Ken Lay. The late boss of the energy trading giant Enron came up with a far more sophisticated fraud than Madoff, with all those "off balance sheet vehicles" that concealed enormous losses. But the net result was the same. Bernie Ebbers, from telecom company Worldcom was found out just a few months later and until Madoff, the $11bn fraud perpetrated by him and his associates was the biggest in US corporate history.

Then we have the bosses who treated their companies as piggy banks. Dennis Kozlowski was jailed for receiving $81m in unauthorised bonuses from Tyco, the conglomerate. Closer to home, but still serving time stateside, we shouldn't forget Conrad Black the former proprietor of the Daily Telegraph who looted his company to fund his extravagant lifestyle.

Just to prove the Americans don't have the monopoly on fraud on a grand scale Italy has provided some of the decade's big business villains, particularly Calisto Tanzi. Tanzi headed Parmalat, a dairy business, which collapsed in 2003 with a €14bn black hole in its accounts. It was dubbed "Europe's Enron".

Still, it's the banking industry from where the real villains hail. British taxpayers will be paying for the mistakes made by its executives for years to come.

First to be indicted into the Hall of Shame must be ex-Royal Bank of Scotland boss Sir Fred Goodwin. He gave back some of that huge pension in the end – the top-up was the ultimate reward for failure – but Sir Fred has not been forgiven.