For those who know Bill Apfelbaum by professional reputation only, it may come as some surprise that he's a tequila drinker. And he's rather partial to the odd pint too.
The Titan boss has distinguished his company among the lunching media world by forbidding any drinking during working hours. But, he insists: "I'm very far from tee-total. It's just a personal belief of mine (not to drink) before 6pm, because it doesn't make good business sense."
So Titan isn't an abstemious, white-shirted corporate android army, then?
Far from it, laughs Apfelbaum good-naturedly, in a manner which suggests he's heard it all before. In fact, he insists, people love working there.
"I'm trying to build a company that's fun and high-spirited, where employees make more money than they could anywhere else and that doesn't feel like work," he says.
The fact that so many of the current senior management originally worked with Apfelbaum at TDI seems to back his claim.
Joint managing director Alison Reay, one of TDI's original "all-star team", is among those to find herself working for the energetic American once again.
"Bill's strategy is, if you're not having fun, you shouldn't be doing it," she says. "But having fun isn't about partying all the time - it's about having fun doing your job and at the end of the day letting your hair down, which we do."
The ex-Yahoo! commercial director says she was tempted back by the chance to work for Apfelbaum again, who she refers to as "a mentor boss". "He's part of the team as opposed to the person dictating what we're going to do," she says. "You'd follow him to the end of the world."
Reay and fellow managing director Andy Moug are the most high-profile UK recruits to have followed him from the "old days", but a substantial part of the management team, especially in the US, all started out together at TDI.
A self-proclaimed Anglophile, Apfelbaum first made a splash in the UK outdoor market in 1994 when he expanded the company from North America and promptly won the London Underground and London bus contracts.
Such early success seems to have set the standard for a career that has spanned over 20 years in the industry - he started selling bus advertising in New York straight out of college.
Just a few years later, he bought TDI, turning it around from "a company that had great assets but very poor balance sheet and bad management" to one that, in the UK, grew its revenue by 35% in its first year alone and owned all the bus advertising in the country.
Having left the firm in 2000, he is now determined to replicate that success with Titan. His rivals admit that if anyone can do it, he can.
Barry Sayer, CEO at Clear Channel, observes: "Unfortunately he's a very good operator; a very dynamic guy. He's a very creative person with huge energy and motivation, and huge financial interest (in the firm) - so he has all the ingredients to drive a business. He's back for 'Bill II'."
A major building block for moving Titan up the outdoor food chain was, of course, the buyout of Maiden back in April. Apfelbaum describes the purchase as "probably the best acquisition I've ever made".
He explains: "What I felt about Maiden was the same as what I found in TDI - great assets, terrible financial troubles because they didn't have a supportive bank group, and poor management."
"It has the best assets in the market - the largest roadside plant, the majority of the rail, all the Network Rail and most of the train operating companies, and the predominant operator in shopping mall and supermarket six-sheets."
Assets in place, Apfelbaum is brimming with confidence about the future - both for the company and the market in general.
"I believe outdoor advertising, which is now 10% of spend in the UK, will be 15% in five years," he says. "Titan has no debt now; we have financial strength. In the first half of the year the company lost money. We will definitely not lose money in the second half of the year, which puts us on target to make pretty good money next year - all sales generated.
"We're number four now - we want to be number one. We want to be the company that invests better, that works harder for the money, that serves better, that spends more on research and new technology and is the most fun to work for."
It's ambitious talk, but as Reay points out: "He always says we should double the industry growth. You think 'oh gosh', but he has complete belief that you can do anything you set your mind to."
For Apfelbaum, that clearly means becoming the market leader. As he puts it: "We have a great marketing team, great management, financial strength - and we're back." CV
2000 Chairman, Titan Worldwide
Officer/director and investor: Maxworldwide, Sunshine Direct, FFM Film Distribution, Channel M, Spotrunner (cable TV)
1989 Chairman and CEO, TDI
1979 President/COO, New York Subways
1977 EVP, New York Subways
1975 Sales manager, New York Subways
1971 Sales executive, New York Subways.