As the arch-fixer/manager/negotiator for one of the most successful commercial sets of chambers in the business, it is no surprise that Paul Shrubsall organised his own exit strategy.

From this October, shortly after he turns 61, he bows out from full-time work as the senior clerk of One Essex Court, chambers of Lord Grabiner, QC, after 44 years of clerking.

“I basically said to chambers, 'This [his handover] is how it should be done',” he said. The upshot is that he becomes a consultant working four days a week for the first year, reducing to three days the year after - and becomes an employee on a fixed salary.

So Shrubsall is not lost to chambers entirely, nor to the world of barristers' clerks. Which must be a relief. Not only has he presided over the growth of One Essex Court, to 67 barristers who enjoy a healthy turnover of £33 million a year, he has been a key agent in transforming the job of the barrister's clerk from the age of the quill pen to hi-tech businesses.

The barrister's clerk is a peculiar breed. Charles Lamb, the 19th-century essayist, memorably described the relationship of his father, a barrister's clerk, with the barrister who employed him, a Mr Salt, like this: “He was at once his clerk, his good servant, dresser, his friend, his flapper, his guide, stopwatch, auditor, treasurer”.

The job is still all those things, Shrubsall says, but these days, much more. The modern senior clerk deals with a large and complex commercial enterprise, a “substantial business in a highly competitive industry”, being responsible for hiring and firing staff; chambers administration; marketing; public relations; and - of course - negotiating barristers' briefs and fees.

It is a far cry from when Shrubsall joined the profession. Just 16, he dropped out of school with only two O levels (“I wanted to do art A level but you needed five Os”) and his father, a managing clerk with a solicitors' firm, steered him towards the law.

He spotted an advertisement for work with G.A.Rink, QC, at 17 Old Buildings in Lincoln's Inn (“barristers were always known by their initials in those days”), where he was paid £8 a week and luncheon vouchers. “The main difference then was the smallness of it all [just three staff] and the slower pace of life. It was a world with no phone, fax, e-mail or computers ... the phone might ring now and again but it was relaxed, very gentlemanly. It was a wonderful environment, formative, lots of time to talk to people.”

What has not changed are the barristers themselves: brilliant, individualistic and often eccentric. He recalls one of his tasks was to dispatch Mr Rink's summer reading books to his hotel in Davos. He also booked the train ticket. The barrister took one look at it: “No, no, no!” was the cryptic response as he strode off. “I found out that he never sits with his back to the engine, and had to rebook.”

Social divisions were more distinct. Shrubsall's senior clerk told him: “If I address someone by their first name, you call them Mr. If I call them Mr, you call them Sir, but if I call them Sir, you don't even talk to them.” The tasks were laborious: he would spend vacations “noting up”, which was annotating law reports that had been referred to in subsequent cases.

Two decades later, all had changed. Shrubsall had a sequence of decisive career breaks that coincided with seismic shifts at the Bar itself.

First, when he was only 27, his senior clerk died and he took over the job: by then the chambers had grown from seven to twelve barristers in a decade. Just two years later, in 1977, three leading juniors in his set (later to become Lord Walker of Gestingthorpe, Lord Justice Chadwick and Peter Whiteman, QC) broke away to start a new set in Queen Elizabeth Building. They invited Shrubsall to be their clerk and he stayed until 1990, by which time it had twenty-one junior barristers, including five silks.

These days such moves are commonplace. In the 1970s it was unprecedented. “Lateral hires [barristers switching] took off in the 1990s but this was the first really big step of its kind. It was ground-breaking.”

It meant he was perfectly positioned to move to One Essex Court as joint senior clerk in 1990 (first headed by Sam Stamler, QC, and now Lord Grabiner - “fantastic people”) at a time when it was growing rapidly, a move that arose from a conversation. It was not popular. “It caused an enormous stir, quite a bit of bad feeling. Yes, there was a fair degree of animosity.”

At the same time, the Bar was changing. The late Robert Alexander, QC, was the pioneering Chairman of the Bar at that time and he organised the first joint conference between the Bar Council and the then Barristers' Clerks' Association (now the Institute of Barristers' Clerks). Shrubsall spoke on the changing role of clerks, pointing out that they were no longer in the days of going round chambers with a coal bucket to make up fires. “I was saved this task - but only by two years,” he says.

Fees had originally all been in guineas; copying was done by hand, in pen. But decimalisation in 1971 and the arrival of VAT in 1973 put an end to guineas, books and ledgers and ushered in modern accounts, he says. By the late 1980s and early 1990s the Bar had seen unrivalled growth. With it came a new professionalism. Being a barrister was no longer just a pursuit for gentleman, he recalls.

No one had articulated this change for clerks before: it led to a code of conduct, proper training, a diploma (clerks all now have A levels and some are graduates), and, of course, it professionalised and modernised the way the Bar operated. Shrubsall was appointed an MBE.

At One Essex Court he put his business-led philosophy into practice and, as is now commonplace, says: “We thought of it as a corporate identity.” A chambers company now buys its equipment and supplies: by contrast in the old days, each barrister would write on a clipboard how many postage stamps or how much sugar he had used. A total of £125,000 a year is spent on marketing and £200,000 on recruitment: new pupils are paid £45,000 a year. “It pays off in the people we get.”

Many chambers rushed to bring in practice managers from outside to handle marketing and the administrative side of chambers, but with mixed success. Shrubsall prefers an in-house head of administration, sitting alongside the senior clerk. “It's not always sensible for one person to do all the work.

“But practice managers have not always worked: they don't know how to handle barristers and after the first year, when the novelty's worn off and they've had the new brochure ... that's when things have gone wrong.”

In all this, though, there is one area where Shrubsall has not moved with the changing times: earnings. In recent years there has been a shift from clerks on commission, who take a slice of their barristers' earnings, to a salary, or a mix of the two. Shrubsall says: “I've always been an oldfashioned senior clerk, and been on a fixed percentage.” He declines to discuss earnings but admits he has had “a very, very good deal”, adding: “There's a lot of merit in having performance-related income.”

He hopes now to spend more time with his wife, two children and three grandchildren, as well as enjoying films, motor racing, fine wines and golf.

But if he is not in the driving seat, he still clearly intends to be on the road. Dealing with barristers (he mentions the “fun and delight” of dealing with Tony Grabiner) has been the best part of the job. “It stresses you, does your nut in, frustrates you, but at the same time the job is so unique that there's nothing else quite like it.

“In the changing role of the clerk, the one constant component has been that relationship between the barrister and the clerk, which is very individual and is still there. You are the keeper of all the secrets.”

Shrubsall, the soul of discretion, will not be rushing to spill them. “It would be a breach of trust,” he says. “You are very, very involved in their lives, all aspects, from ordering flowers if an anniversary is forgotten, sorting out Christmas cards, dealing with wives ... all in a supportive way. “

“It's a great partnership between very clever people, not always with common sense, and people like me who are not necessarily very clever but do have common sense. It's very special and I have loved it.”

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