How Bet365's Denise Coates hit her own jackpot
Denise Coates, the billionaire boss of Bet365, added another £323m to her wealth this week after the company her family founded racked up another year of huge profits.
She's been called the UK's most successful woman, with a fortune that Forbes magazine puts in the region of £9.3bn.
Most strikingly, she has made that largely herself.
Bet365 is Stoke-on-Trent's largest private sector employer, with more than 4,600 staff. It offers its millions of worldwide customers sports betting, poker, casino, games and bingo. The firm had a £3bn turnover in the year to the end of March and a profit before tax of £791m.
Ms Coates' brother John is joint chief executive and her father Peter is the firm's chairman, but Denise Coates owns half the company and there's no doubt the success is largely hers.
Serious gamblers tend to have a "system", a supposedly foolproof method that will keep on bringing rewards. So what's her "system"?
Go back to the 1990s and there aren't many who would have gambled on the small family-run chain of local betting shops growing to such a size.
A lot is down to her mathematical talent, which was remarkable from an early age. David Owen taught her at secondary school in the 1980s.
"She got everything right, only asked pertinent questions and was angelically behaved. She was clearly off the scale. If we were talking Mensa, she'd be in the top 1%," he told the BBC.
She achieved a first-class degree in econometrics and trained as an accountant within the family firm, building further on the knowledge of the small chain that she picked up while working part-time during high school.
As well as a very keen eye for figures - the heart of any successful bookmaker - she is also a moderniser.
One of her colleagues, Debbie Tatton, told the BBC: "When Denise came, she wanted a closer relationship between the staff and the customers. We became a lot more professional, a lot more customer-focused. A lot of younger people started coming in, as well as a lot more ladies."
In 2000, Ms Coates upped the stakes and persuaded the family to mortgage the business to allow them to develop new software.
Her brother says she became fixated on the potential for online gambling and became a pioneer in that business.
Setting up headquarters in a temporary building in a car park, Ms Coates called it the ultimate gamble, buying the domain name Bet365.com so that she could drive the business in that direction.
"She's highly intelligent and very determined," says Warwick Bartlett, from global betting and gaming consultants GBGC.
"She is also capable of looking at the big picture. Betfair was the innovator in in-play betting, but she was basically the first to harness mobile technology, recognising that gamblers anywhere would be able to bet on sporting events."
A huge 70% of income now comes through betting on tablets and phones.
She is helped, Mr Bartlett says, by the fact that she, uniquely, really knows the industry. "The Coates family are third-generation bookmakers. They have learned the business from parents and grandparents.
"She has an innate knowledge of what the gambler is looking for. A lot of the companies these days have managers that may have come from [other sectors]. They are professional managers who try to apply their knowledge gained from selling beans or margarines."
Mr Bartlett says close knowledge of another business has helped with the in-play football income: Bet365 owns local club Stoke City.
"Owning a football club gave them an insight into the way the Premier League worked. Stoke City, not so successful itself, has played teams that really are," he says.
"On top of the contact with the professionals they benefit from coverage through the sponsorship of the team. Bet365 has great exposure every time Stoke are featured."
Ms Coates' father is chairman of Stoke and has a higher public profile than she does.
But the name best associated with Bet365 is, of course, Ray Winstone, whose gravelly tones used to urge punters to "bet in play - NOW!" before the ads were pulled.
Again, Warwick Bartlett says, Ms Coates got it right. "Using Ray confirms my point about 365, they know their customers. He's a middle-aged guy and a bit of a geezer.
"Cleverly, Bet365 use similar types to appeal to their customers in other markets. In Australia, it's Samuel L Jackson - he comes across in the advert as a very cool guy."
Bet365 continues to keep one step ahead. It's moving into the US as the market there opens up.
But while Denise Coates' business brain thinks global, she herself is likely to remain rooted in Stoke.