IAIN Robertson cannot remember now exactly how much Royal Bank of Scotland lost when US energy giant Enron collapsed under a huge fraud, but the topic is enough to cause his hallmark "measured" demeanour to evaporate.

Otherwise, Robertson is in absolutely fine fettle as he prepares to retire later this month from Royal Bank's board after more than 12 years. And so he should be, given he has built a spectacularly successful corporate banking division which was pivotal to Royal's transformational - pounds21bn acquisition of National Westminster.

He also brought electronics giants such as Motorola, NEC and Hewlett-Packard to Scotland during his days with inward investment body Locate in Scotland and its parent Scottish Development Agency, and still speaks with great passion about his role as chairman of the 1988 Glasgow Garden Festival.

Robertson, who was nicknamed the "Bald Eagle" during his days as a civil servant, confesses he "hates losing money".

And he loathes breach of trust - especially given the relationship banking model he has created at Royal involves getting close to customers.

Even though the hundreds of millions of pounds Royal has been seeking to recoup following Enron's collapse is not crippling in the context of the many billions earned over the years by the Edinburgh institution's wider corporate banking business, the scandal really rankles with Robertson.

He says he found Andrew Fastow, the former Enron Corp chief financial officer who has pleaded guilty to two conspiracy charges in exchange for a 10-year prison sentence, "very plausible" when he spoke with him.

Most of Royal's exposure to Enron was inherited with its takeover of NatWest in 2000, but it did a few pieces of business with the energy giant after this deal.

Robertson, who is lauded by Royal chairman Sir George Mathewson for his "measured" and "considerate" nature as well as his undoubted intellectual capacity, understandably takes exception to the Enron fiasco.

The 59-year-old corporate banker, who is in his house in Val do Lobo (the Valley of the Wolves) in his favoured golfing territory of Portugal's Algarve, is surprisingly frank about Enron when asked about the experience.

"NatWest had some fairly heavy involvement, " he says. "We did a number of transactions with them.

We applied the kind of principles that I have applied right through the time I have been in banking.

We applied all the same principles:

have a look at the credit, work out where you get the money back."

Robertson, as well as being exceptionally bright, is also thorough, and this is undoubtedly a key factor in the track record he cites of building Royal's annual corporate banking profits from about - pounds60m when he joined in 1992 to - pounds3.3bn by 2002. Around the start of 2003 he handed over day-to-day responsibilities to Johnny Cameron, but continued to chair a corporate banking and financial markets division which turned in profits of - pounds4.3bn last year.

So he is not a man who is easy to hoodwink.

"It was as big a shock to our system as to anyone else's systems at the back end of it (Enron). There was such appalling manipulation going on in it. You kick yourself. I hate losing money. We lost money in that one in a big way.

"I have always dreaded well thought-out fraud more than anything else. That is one of the hardest things to guard against in any business environment."

Fastow was the most senior Enron executive with whom Robertson talked ahead of the giant corporation's collapse into bankruptcy on December 2, 2001.

Robertson says: "I think the only director I spoke to was probably Fastow, who was a very bright, very plausible individual, I have to say. I have spoken to a variety of other people.

"It wasn't very long after we took over NatWest that things started to go wrong. I think we did three things from the time we took over NatWest to the time it all imploded. By the time it did implode, I think we were more than a little suspicious about whether this thing could keep flying."

On the extent of the losses, which are signalled at about dollars -537m by Royal's claim in the bankruptcy case, Robertson says:

"If you ask me how much it was, I actually couldn't tell you any more.

It was a lot of money."

He views the ultra-strict Sarbanes-Oxley Act in the US as an "over-reaction" to several huge American accounting scandals which started in earnest with Enron.

And he is doubtful as well about whether it will make much difference to the criminally inclined.

Robertson says: "I always think when you have reaction in these situations you tend to get overreaction. I think Sarbanes-Oxley has got a measure of over-reaction in it. How far it will work and how far it will not work will be interesting to see. I have this horrible feeling that someone who is absolutely determined to perpetrate a huge fraud - I am not convinced Sarbanes-Oxley would stop it."

It is no surprise to hear the principled corporate banker declare: "I just hate fraud."

In contrast, and in line with his generally optimistic outlook on the world, Robertson makes plain during the interview his delight in dealing with customers.

The first thing he did when he was headhunted to Royal by Mathewson in 1992 was to get out and meet the customers, who told him they believed the bank had good people but at that stage an insufficient range of products.

"I think that I actually built up what I believe is the best relationship bank in the UK, but arguably the best corporate relationship bank world-wide.

"When you build that up and try to create an open, deep, meaningful relationship with all your major customers, when someone arguably takes advantage of it, when someone actually abuses that kind of relationship and that sort of trust, it upsets me big time.

It is a breach of ethics, morals, anything you want to call it, as well as being downright fraudulent."

Robertson, in spite of the huge responsibility he has shouldered as head of a massive operation, repeatedly describes business as "fun" in an enthusiastic tone which signals he genuinely means this.

He has clearly enjoyed working with Mathewson, the man who effectively took the reins of a troubled Royal in 1990 and turned it into the world's fifth-largest bank.

"George and I celebrate our 25 years this year, which I find absolutely staggering, " says Robertson who, as a civil servant at the Scottish Office at that time, first encountered Mathewson when the Royal chairman was at the SDA.

The reason for their meeting was trouble at engineering group Weir, which set up shop in Victorian times in Cathcart on the south side of Glasgow.

Robertson recalls: "I first met George very soon after he joined the SDA . . . when Weirs were having their well-publicised troubles right at the end of the seventies. We worked quite hard and quite well on that one for quite a while. It came out of its problems. There was a rights issue we had managed to have underwritten. It managed to get away. It has been forward ever since."

It was an early portent of how the pair would link up to great effect over the next quarter of a century.

Dunbartonshire-born Howard Macdonald, who had turned around Canada's Dome Petroleum and was brought in to sort out the troubled County NatWest in 1989, sought Mathewson's views on Robertson when he was looking for someone to help turn around the investment bank.

County NatWest was reeling from allegations of fraud surrounding its handling of a rights issue for Blue Arrow in 1987, which saw the bank stuffed with 10% of this employment agency's stock which was by 1989 worth about half of the original issue price.

Mathewson, who had been succeeded by Robertson as chief executive of SDA in 1987, says: "I had been asked by Macdonald about Iain. I said they could do no better. Iain became finance director and then deputy chief executive at County NatWest. He had a lot to do with sorting out the problems from Blue Arrow."

The scale of the problems at County NatWest are still fresh in Robertson's memory.

"County was frankly still reeling from Blue Arrow. (It was a) bit of a shock to the system when I went (in, in 1990) and found they were losing something over - pounds65m-a-year when I joined. I was there for two years - which was as brutal a period as you could imagine.

They actually broke even in the quarter I left."

Robertson's performance at NatWest left Mathewson in little doubt about who he wanted to build Royal's fledgling corporate banking business when looking for a successor for John Barclay in 1992.

Mathewson, who took time out of a skiing holiday this week to tell The Herald just how highly he rates Robertson, said: "Throughout my career, I have always noted in the back of my mind people of outstanding ability. Iain certainly was that. (With) the experience he got at County NatWest, he (Robertson) was just an obvious target to come (to Royal)."

Robertson remembers the call to Royal well.

"He (Mathewson) said: 'We have a nice little corporate bank which makes - pounds60m a year. I think we can get it up to - pounds100m within three years.'We got it to - pounds500m, I think, about 96 or 97 (then) along came NatWest."

Robertson, who is fulsome in his praise of the efforts of his team at Royal in taking on NatWest's corporate bank, says of NatWest at the time of the 2000 takeover: "I knew they hadn't got past the bad old NatWest problems. Some of the initiatives that started in 199192 were still running when we got to the takeover of NatWest."

Not everyone who required Robertson's services was as lucky as Royal, however.

Before Mathewson stepped down as chief executive of SDA in 1987, Robertson had had his leaving party as he prepared to join ScottishPower (formerly South of Scotland Electricity Board) as finance director. When Mathewson went, he found himself propelled into the SDA hot seat.

He talks with passion about his time at the head of Locate in Scotland in the mid-eighties and then at SDA - declaring this highly entrepreneurial organisation with all its infrastructure capability had "almost changed the balance of the employment structure in Scotland" as it reeled in the big players in electronics and healthcare.

He laments the changes to the SDA, which he describes as "the envy of enterprise agencies throughout Europe". Successor body Scottish Enterprise in some ways has less flexibility in targeting particular areas than the SDA given SE's extensive local enterprise company network, and industrial property is no longer a key function of the public sector development agency.

Robertson spends about eight to 10 days a month on business matters as a non-executive director of Royal, chairman of British Empire Securities and General Trust and of "very specialist" Edinburgh fund management boutique Cairn Capital, and as a non-executive director of John Menzies.

He will devote some of his semiretirement, during which he will still assist Royal on big-ticket deals, to improving his "awful" golf handicap of 17.

It is on the golf course that Robertson's famous big brain sometimes lets him down.

He says: "I probably start to think too early in the round.

Whenever I start to think about it, my brain goes. I wander off and don't manage to maintain concentration or something like that."

Married to Morag, he has four grown-up children, two boys and twin girls, and two grandsons, with another grandchild due in July.

"It is good to be wanted for babysitting, as they say. My wife loves the grandchildren. I love the grandchildren as well. I think, like most women, they twist her round their little finger. They do."

So how will Robertson feel when he steps down from Royal's board at its annual meeting in Edinburgh on April 20?

"It will be a moment of lots of regrets . . . I leave it in extraordinarily good and extraordinarily competent hands. What else could I ask for? If I had another 20 years, life would be different. I don't. You have got to get on with it. You get on with the next phase of your life."


Career highlights: Head of inward investment agency Locate in Scotland. Chief executive of Scottish Development Agency. Chairman of Glasgow Garden Festival. Turning round County NatWest after Blue Arrow rights issue debacle. Appointed in 1992 to build Royal Bank of Scotland's corporate banking business Best moment in business: "The time in inward investment . . . The (Glasgow) Garden Festival, I loved that. Being given the opportunity to grow a large corporate bank. It has to be the dream you could never possibly have expected."

Worst moment in business: "Of course there have been moments that are not good. Could I give you a list of half-a-dozen worst moments? I couldn't, off the top of my head."