"What should a partner be? Why can't somebody be called a partner who is working from home for two days a week, or two years?"

Norton Rose Fulbright chief executive Peter Martyr has turned his attention firmly inwards after the string of international mergers that created his firm, and is now on a mission to transform how its staff and lawyers work, putting flexible and agile working at the heart of a strategy aimed at driving global efficiency and transforming the business.

At the centre of the plans is a new multimillion-pound global practice management system from SAP, which will ultimately look after every aspect of the business, a new back office in Manila and a legal services centre in Newcastle that launched in April this year.

But the changing role of Norton Rose's people as part of this shift in working practice is also on his mind.

"We have experienced tremendous growth in the past five years and have completed the majority of the geographic expansion," he says. "In the last 12 months the firm has undertaken measures to complete the level of integration necessary to succeed in an increasingly disrupted legal market.

"By 2020, we will have our global practice management system in place, which will enable us to manage an agile workforce that will have a combinations of parts to it: low cost centres, grey workers, and the future possibility of different types of partners – all of which will be joined together by a single system and cost managed effectively," he continues.

Martyr, who also held the Norton Rose LLP managing partner role between 2002 and 2015, when he handed over to Martin Scott, is speaking from experience when it comes to creating opportunities for his people.

While many City law firm leaders slashed jobs during the global financial crisis of 2007-09, Martyr saved 100 roles through a high profile flexible working scheme that avoided redundancies by reducing lawyers' hours. At its height in summer 2009, Flex saw around 600 staff working reduced hours.

Since then, however, the firm has been through a succession of major mergers. It merged with Australian firm Deacons in 2010, then in 2011 with Canadian firm Ogilvy Renault and leading South African firm Deneys Reitz. These were followed by a second Canadian merger with Calgary's Macleod Dixon in 2012, while legacy Norton Rose's union with US firm Fulbright & Jaworski went live in summer 2013. More recently, it inked a deal with Vancouver-based firm Bull Housser & Tupper last month.

The growth has been so flat out that some City partners began to feel isolated and detached from the firm's strategy, according to former partners, but Martyr now seems keen to rectify these issues.

While a WeWork setup with unlimited beer on tap may be some way off (and indeed unnecessary for lawyers who already have access to their own bar in the staff canteen), Martyr says floor space at the firm's striking London Bridge headquarters will change along with working practices.

"The office will change and become much more informal. Our [London] accommodation will definitely change. The style will change too and that will be the biggest challenge. That's not going to happen in five years but over time we'll have to cater for different plans."

Martyr says that until recently, Norton Rose, like other UK firms, was expanding in London. "This may change now the tech revolution is upon us. When we took on our office we split the building up, so we have the ability to engineer our space."

Agile working will aid the shift in working practices and space requirements. Often used interchangeably with flexible working arrangements, which are individually negotiated, the term involves staff using technology to work any time, anywhere, provided business needs are met.

Why does a partner have to be just based in the office? It's only a question of money

"We are looking at the question of agile working to determine how best to promote this as part of our culture and make it available to everyone," says Martyr.

As part of this, the firm's partnership structure is likely to come under scrutiny and ultimately change. Says Martyr: "If you're basing your business on a more agile model, surely everything should have that agility, so why doesn't that apply to partnership?

"We all in London have a very traditional view of an equity partner: you're an equity partner or a salaried partner – but why does a partner have to be just based in the office? It's only a question of money."

Martyr is also adamant that the firm needs to put "significantly more effort" into boosting its ranks of female partners to ensure that the proportion hits 30% by 2020. He points to the way the male-dominated City, including its lawyers, tends to club together in ways that may exclude women.

"There continues to be a 'club system' that definitely operates in favour of men. We need to ensure women and members of other under-represented groups receive equal access to clients and client opportunities," he adds.

Greater employment opportunities for older workers will also feature.

Underpinning all of this is seamless integration after years of aggressive expansion. "It is essential for our business that we invest in the integration of our global systems and infrastructure, and develop the means to operate and practice in a more agile manner," Martyr stresses.

Cue SAP. The software giant employed by the likes of FTSE 100 companies such as BP and Shell will now be rolled out across the Norton Rose network. Its 3,800 lawyers, including 912 equity partners, will all use it, with the system to ultimately control all of the firm's data – from payroll, expenses and billings, to time recording, client data and analytics. Its uses could include examining how an individual deal is being managed on a day-to-day basis and the cost and profit of that deal. It will also be possible to work out how profitable – or otherwise – various parts of the business are, from whole offices to teams, regions or industry sectors.

By 2020 or 2025, could we be in a different structure? Yes

The first phase of the rollout will kick off a year from now and take approximately six months. The second wave will follow swiftly after, says Martyr.

"It's a major investment. We have a load of systems that cost a lot of money to repair. We could have continued to do that but we would have spent a significant amount of the cost of the new system.

"Our plans for creating a more flexible workforce depend on being able to manage the disaggregation of our work product and having seamless communication across all of our offices."

So will Martyr be able to secure the buy-in from restless partners into his forward thinking? And, crucially, will he finally be able to harness the change to produce a more efficient workforce to boost profits?

Money has long been an area of contention for Norton Rose, which has struggled to turn the huge revenue growth that has come via its mergers into bottom-line gains. The firm does not provide a global profit per equity partner figure, but estimates from Legal Week US sister title The American Lawyer suggest a figure of £392,000 for the 2015 financial year, up 3.5%.

Market whispers of imminent potential financial integration between the Swiss Verein member firms are dismissed for now. "There are no particular plans for that but if we find a more convenient business model, absolutely we'll look at it. By 2020 or 2025, could we be in a different structure? Yes."