The anti-smoking guru Allen Carr, who has died from lung cancer, was a controversial figure.
Deborah Granville used to smoke 20 cigarettes a day
A former 100-cigarette-a-day man, his methods were designed to help people recognise what made them smoke, and therefore help them stop.
But anti-smoking campaigners said they were disappointed Mr Carr had never subjected his technique to scientific evaluation.
After Mr Carr quit smoking in his late 40s, he became a "convert" who wanted others to stop too.
He built up an empire of 70 clinics in 30 countries, and sold more than 10 million copies of his books worldwide.
Amanda Sandford of Action on Smoking and Health said: "His method was basically a form of cognitive behavioural therapy. He talked to people and tried to make them address their rationale for smoking and what the triggers were which made them have a cigarette.
"It was certainly popular, and it did seem to work for many people.
"But he would not subject his work to independent review, so it was difficult for scientists to make a proper evaluation."
Mr Carr also believed that nicotine replacement therapy was ineffective, although scientific studies have shown it helps people quit smoking with almost double the rate of success than going "cold turkey".
But Deborah Granville, who quit using Allen Carr's 'Easyway' method, said it was the only thing that had worked for her.
Allen Carr was a controversial figure in the anti-smoking establishment
She had smoked around 20 cigarettes a day since she was 17.
However, when she reached her early 40s, a combination of her mother's death from a heart attack, a friend having breast cancer - and pressure from her children, then aged eight and six.
"I did try other methods. I used acupuncture, and giving up just using willpower.
"But neither worked, and I felt awful when I relied on willpower.
"I read Allen Carr's book. But it was going to the session which really helped me.
"It was a four-hour session, where we all smoked, and it was really based on the repetition of certain phrases which reinforced the idea that you were making a positive choice.
"It was about freeing yourself from something, rather than giving it up."
Deborah added: "The first couple of days weren't easy, but they weren't terrible. And I haven't had a cigarette now for over 10 years."
Ruairi O'Connor, of the British Heart Foundation, said: "Estimates of the huge numbers of people helped by Allen Carr programmes show his methods provided a valuable service to help people quit.
"We hope that his memory will continue to inspire people in their efforts to give up smoking."