Stella English has been named the winner of The Apprentice, beating Chris Bates in the final.
English, 31, was told "you're hired" by Lord Sugar after a task in which she and Bates, 23, created and marketed a new brand of alcoholic drink.
"I'm on cloud nine and my feet haven't really touched the ground," she said.
The pair led teams made up of former contestants, among them Joanna Riley and Jamie Lester - both of whom viewers saw "fired" earlier this week.
The finalists were asked to choose flavours, design a bottle and film an advert before pitching their product to industry experts.
English, head of business management at a Japanese bank, said of the competition: "There were times that I felt very tired and it was much harder than I ever thought it would be. But in terms of quitting, there was absolutely no way."
She said she hoped to provide a "better quality of life" for her two young sons.
During the task, English, who grew up on the Thamesmead estate in London, complained that she faced strong opinions from her team.
"Everyone likes to have their opinion and make themselves heard," she said. "That's what my team like doing."
Lord Sugar said choosing between the finalists had been a "tough decision".
English will be employed at one of his companies, Viglen, which provides IT services.
"It's a very, very important job where you need a very, very good organiser and someone who's very, very switched on. She's got the brain to do it," Lord Sugar said.
He said he would be happy to discuss potential employment with Bates.
'Irritating' team mates
"He's young, he's got no real experience but he's a very quick learner and I think he would be useful," he said.
During the final task, investment banker Bates became angry when team members defied his wishes to make the drink pink rather than clear-coloured.
"I don't mind winning or losing by the decisions I make," he was seen fuming.
"But when they decide to take it upon themselves to make decisions that I didn't tell them to make, I do find it quite irritating."
The sixth series of the popular BBC One show began in October this year, making a star of garrulous runner-up Stuart Baggs "The Brand".
It was postponed from its customary spring slot after concerns were raised over Lord Sugar's role as a government advisor at the time of May's general election.