You don't forget the first time you meet Tommy," sources say, scrambling for words to pin down his personality. "Gargantuan." "Blustering and charismatic." "Gregarious." "For an American, a big drinker."
Another character trait could be "accessible". To some surprise, our call was picked up by Tom Carroll, the newly appointed chief executive of TBWA\Worldwide, himself.
Caught on the hoof, he makes no apology, insisting that he likes to pick up his phone to all, and agrees to an interview instantly, without even running it past a press officer.
Also known for his charisma, it is Carroll's leadership and management flair that underpins some of TBWA's most important global client relationships, including Adidas, Absolut Vodka and Masterfoods.
Carroll, like Jean-Marie Dru, the TBWA\Worldwide chairman who he will be replacing in his new role (and who he has worked in the network with for years), has TBWA in his blood. He has seen it evolve from a group of disparate companies into a defined global offering.
He honed his craft at Chiat/Day in the 80s, and returned to the network at the end of the 90s as president of the Los Angeles office.
In 2001, Dru took the reins as TBWA's president and chief executive following the merger of London's GGT and Paris' BDDP, and both he and Carroll set about the transformation of TBWA.
Barely seven years on, and the network is in pole position, trumping many of its rivals who have struggled to carve out a distinct global identity. In the US last year, TBWA added nearly $500 million of new business, while Apple, Adidas, Mars and Nissan are among the global brands producing compelling creative work in each of its regions.
Although Carroll is to step into Dru's shoes, the differences between the Frenchman and his fiery American successor are stark.
Dru, statesmanlike and chivalrous, is often described as a quiet thinker. He was the founding father of Disruption (TBWA's planning process), and his ideas have given TBWA a strategic depth alongside its creative flair. Carroll, more a suit by trade, is better known for his ability to forge deep client bonds and an intuitive judgment that has often strengthened them.
"Tom's biggest asset is his self-awareness," Carl Johnson, the Anomaly founder and former president of TBWA\New York, says. "He is not an arrogant American, and is smart and worldly enough to concede what he doesn't know."
"Dru was an intellectual and cerebral theoretician, whereas Carroll is more of a heart player," Farah Ramzan Golant, the chief executive of fellow Omnicom agency Abbott Mead Vickers BBDO, says. "In a world of compromise and pragmatism, he's not afraid to take a view and defend it to the death. Tom will help TBWA to reinject its sense of self-belief."
Carroll describes his first task as figuring out "how to build on current momentum and accelerate growth across the network" while paying closer attention to the areas that need it. "It is testament to how far we've come in eight years that we're delivering Disruption all over the world," he says. "The question we've got to keep asking is how do we continue to engage audiences through ideas that are powerful and relevant?"
Just how involved Carroll will be across the network is debatable. It is no secret that Dru flew tirelessly around the world bringing the network together, particularly at the earliest stages of the merger.
Carroll, whose advertising experience is entirely US-based, is more likely to listen intently to his global team: Keith Smith, the international president; Robert LePlae, the president of North America; and Perry Valkenburg, the chief operating officer, international and president of Europe.
As one colleague puts it: "Carroll will get as close as he needs to network problems, so if (the Omnicom president and chief executive) John Wren presses him, he'll know the answer. But he will rely on his team to raise and resolve those issues; he is not going to be flying from region to region like a messiah."
Either way, he will be faced with some tough questions over the next year. While the network has shown global cohesion and world-class creativity in its stock-in-trade - advertising - the integration between group companies such as Tequila, Agency.com and Integer, as well as the significance of Media Arts Lab (its creative hub for Apple), has varied from market to market. In Asia, for example, many of its offices are newer operations and appear more closely aligned than its European counterparts.
"As the world changes, the move from advertising agency to communication network is at the top of every chief executive's agenda," a former colleague says. "How it makes that change without just reshuffling management within an existing group structure has still not been answered. Carroll needs to build a progressive leadership team that will address the bigger theoretical issues than staff. He's got thousands of people, existing countries, cultures, structures and paperwork all firmly bedded in place; how do you reorganise that into a new structure that is reflective of the time?"
Certainly, the UK is one such example. Tim Lindsay was appointed as the president of the UK & Ireland last year with the remit of bringing the relationship between TBWA and its group companies Stream, Tequila, TBWA and Agency.com closer together.
This is still work in progress. But reports last year that Agency.com and TBWA had failed to implement their proposed integration and that the digital network was pulling away from TBWA rumble on. Both Lindsay and Carroll dismiss this, however, insisting the digital arm "is still part of the TBWA group and will continue to be".
"The question we're asking is what do we need to do to engage audiences?" Carroll says. "Media Arts and Disruption are unifying concepts that allow us to focus on the issues facing brands and their audiences regardless of which company is doing it. Delivery of an idea's easy, it's having the idea that's hard."
He remains philosophical about the wider performance of the London office, insisting it's bouncing back towards its halcyon days of the late 90s. Denying that the management gaps were not plugged soon enough following the departure of key players such as Trevor Beattie and Andrew McGuinness in 2005, Carroll views London as a vortex for good talent that "you just have to reload". "London tends to have a faster drainage of talent than any other market," he says. "We've now got a good management team in place in London under Tim, and it will update itself in time."
Carroll also points out that the network is still in its infancy: "We came together eight years ago. We're constantly asking what is the best way to engage audiences and making changes to reflect that. We're now in a place where news, information and ideas flow across the network regardless of where in the world they first came from."
And he remains adamant about his future at the helm. "New York is doing well, LA, Germany and Holland are better than ever, Asia is healthy and the UK is coming back. I'm certainly not taking over something that's broken."
Lives: Rye, New York
Family: Wife Kathleen, Ryan Anthony, six, Julia Marie, four
Favourite ad: Skittles "sheep boys"
Most treasured possession: My Jay Chiat sculpture
Favourite website: Webkins
Interests outside of work: Skiing with my wife and kids (the right thing
to say), golf with my friends (the right thing to say)
Motto: Life is short but wide