It's hard to place Stephen Lussier's accent - he mostly sounds British, except that he rolls his Rs. "The Americans think I'm English and the English think I'm Canadian. I think I'm lost somewhere in the mid-Atlantic," he laughs.
That the Boston-born 56-year-old has shed most of his American accent is unsurprising; he has spent over half his life in London, working his way up from the very bottom of the diamond giant, De Beers. Today, he is the group's executive vice-president of marketing, and chief executive officer of its premium diamond brand, Forevermark.
"I'm still amazed in some ways that when I look back on it, my life has gone in that direction. Although each time through my career at De Beers, there have been opportunities to think: 'Well, what do I do next?', something more interesting within the company has always come up. So I kept pursuing it, and in hindsight it seems like it was a good decision."
As a self-described marketer at heart, Mr Lussier has found his dream job in De Beers, which was founded in South Africa in 1888.
Despite studying psychology at Boston College, he decided against furthering his studies in the field to become a clinical psychologist.
"I thought that was probably not for me, because I just didn't think that I'd like the day-to-day existence of working with people who needed help. I didn't think I was a good helper, but I was fascinated (by the way people thought about things).
"So I found sort of the opposite end of the spectrum, which is to use that same interest in the deeper levels of people's motivations, but to use that in a commercial way. That's why I think I ended up in advertising, and why I gravitated to the world of luxury where you have to peel back the layers of motivation - and then use that understanding to build a brand."
After earning an MBA from Columbia University in 1981, Mr Lussier again decided to take the less trodden path. While most of his peers went off to Wall Street, he joined what was then America's oldest advertising agency, NW Ayer.
"I joined the advertising agency because I thought it would be fun and fascinating. I've often made my decisions in life based on what I thought would be interesting at the time, rather than whether it was particularly good on a CV," he says.