Paul Maher is a man in a hurry. A few days before Christmas, the vice chairman of Mayer Brown, a law firm formed in 2002 by the merger of Mayer Brown & Platt, based in Chicago, with Rowe & Maw, based in London, announced another international marriage — this time with Johnson Stokes & Master, one of the biggest firms in Hong Kong. In one stroke, it gave Mayer Brown a foothold in Asia it had set out to achieve over several years. But Maher, who personally oversaw the deal, still isn’t satisfied. “There are still bits of the globe we’d like to be in,” he says.

The JSM merger capped an eventful year. Mayer Brown restructured and rebranded, dropping Rowe & Maw from its name and, somewhat more painfully, 45 lawyers from its partnership. In London, there has been an ambitious recruiting drive, with partners lured from rivals such as Ashurst and Barlow Lyde & Gilbert. Its impressive new offices at 201 Bishopsgate are nearing completion. In the US, there were accusations of professional negligence over the collapse of Refco, the futures broker. Lately, the firm has been knee-deep in the fallout from the credit crunch. At least life is never dull.

Maher (pronounced, fittingly, May-er) is 48, but seems younger. His manner is informal, his light hair ever so slightly dishevelled, and he exudes a calm, almost preternatural self-confidence. As a teenager, he kept a poster of Che Guevara on his bedroom wall, dreamed of being a war journalist and played guitar in a New Wave band with his younger brother, channelling The Clash and hawking demo tapes around record companies. He still owns a guitar but these days is more likely to be found playing football on Saturday mornings near his home in Wandsworth Common in south London, or watching it at Chelsea, where he holds a season ticket.

Maher made his name as a corporate finance lawyer, but now, as part of a management troika headed by chairman James Holzhauer, in Chicago, devotes much of his time to implementing the firm’s global strategy. It is a position of genuine influence enjoyed by few other English lawyers at US firms in London. (Maher resists the characterisation of Mayer Brown as an American firm; he finds it “irritating”.)

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Maher's strategy essentially amounts to: grow, grow, grow. Mayer Brown now has more than 1,800 lawyers across the US, Europe and Asia, generating revenues of $1,084 million last year, according to Legal Business, a trade publication. That is equivalent to $770,000 per lawyer, less than Chicago rivals such as Latham & Watkins and Kirkland & Ellis but more than top-ranked English firms such as Allen & Overy and Clifford Chance. But Maher wants to be bigger, more profitable. “We want to be one of the big elite law firms of the world,” he says. In London alone, he is aiming for 60 to 70 per cent growth over the next three years, with billing expected to more than double to £200 million.

Maher's determination stems from a conviction that high-value legal work will come to be shared among a handful of huge, global full-service firms on one hand and a few smaller, high quality specialists on the other, with the rump of firms left in the middle eventually squeezed out.

He predicts there will be increasing consolidation as these middle-ranked firms strive to achieve the scale they will need to survive, either by merging or — now that the restrictions on accepting outside investment have relaxed — raising capital on the stock market. “I’ve been saying it for a decade and people have quite literally laughed at me,” he says, “but law firms will float.” Asked point-blank if Mayer Brown is considering an IPO, he fudges, but doesn’t rule it out.

Maher has not always been so single-minded. Born and raised in north London, the son of a shipyard worker from Liverpool, he was the first person from his family to go to university. He read law at Bristol, putting aside his dreams of becoming a journalist, supporting himself with jobs on building sites in the summer. After graduating, he took a job as a solicitor at a sleepy private client practice in Mayfair, qualifying in 1984, but soon joined the in-house legal department at ICI. There he learnt a lot about business, he says, but it was hardly the fast-track to stardom and after five years he felt his legal skills were beginning to soften. “I thought I’d go and see if I could hack it back in private practice for a while,” he says.

In 1990, Maher joined Rowe & Maw, impressed, he recalls, by the partner who interviewed him: Charles Ashcroft, who later became general counsel at EMI. One of the first deals he worked on was the $1 billion sale of Virgin Records by Sir Richard Branson to EMI. He was, by his own admission, a combative dealmaker — “No-one wants their lawyer to be a nice guy,” he says — and was made a partner two years after joining the firm. But by the end of the decade, he had become frustrated at Rowe & Maw, feeling it was too rooted in its ways. The world was changing. “We knew that the business needed to be significantly internationalised in order to survive,” he says.

In 1998, Clifford Chance offered Maher a partnership, and he accepted. It took the then-senior partner Stuart James and a promotion to head the corporate department to persuade him to stay with Rowe & Maw. In 2002, when James announced he was stepping down, Maher was elected senior partner with a mandate to shake-up the staid mid-market firm.

Before he took up the post, however, Rowe & Maw was approached by Mayer Brown & Platt. Maher was sceptical, having already entertaining overtures from several American firms. But he quickly discovered chemistry with his counterparts from Chicago. The perception of cultural differences between English and American lawyers is overblown, he says. “Frankly, things don’t break down on cultural lines. They tend to break down on business philosophy lines. There are those who want the fast approach to life whether they’re in London, Germany, Washington or Houston, and those who are much more cautious by nature.”

Cautious Maher is not. But whether he can lead Mayer Brown into the handful of top firms in Europe, as he intends, is far from certain. Some of the competitors he will have to step over are bigger, longer established and run by similarly bright and determined leaders. And as those competitors are quick to point out, achieving rapid growth in revenue and head count is one thing; maintaining quality is quite another. Already there are whispers that some of Maher’s American colleagues are worried he is taking them too far, too fast. A recession is looming. Maher is unlikely to be deterred.

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