I have fought the tobacco pandemic for decades and now, at the age of 70, I have no intention of ever retiring.

I have just arrived back from Beijing and Pyongyang, and my global travels to curb smoking will continue.

I work predominantly with governments, as only governments can introduce tax policy, ban advertising, legislate for smoke-free areas, and mandate mass media campaigns.

I never tell governments what to do. I supply information and statistics to support their decision-making process, but they are responsible for whatever decisions they make.

How do the tobacco companies react? As you might expect - with anger, hostility and threats of lawsuits.

Their trade organization once described me as one of the three most dangerous people in the world, which, coming from them, is a rare compliment.

How did I get into this, and why is my work, though international, largely focused on Asia?

I moved to Hong Kong in 1967. I worked for over a decade as a medical specialist in government hospitals. But I realized that treating hospital patients was like putting on a band-aid: We could patch them up but seldom save them. I just saw too many smokers die. I realized that what was needed to save lives was prevention, not attempted cures.

In the 1980s I became involved in the fight for equality for women, undertaking Asia's first study on domestic violence, and helping set up the first rape crisis counseling service and a refuge for battered women.

I realized that tobacco was a women's issue, affecting women's health, and that the tobacco companies were exploiting women with messages of emancipation and freedom.

In the 1980s I began writing a column on women's health for a local newspaper, and one of my early topics was smoking. This roused a fierce reaction.

A major international tobacco company prepared a dossier saying: "The anti-smoking lobby (only myself at the time) in Hong Kong is largely anonymous, unidentifiable, entirely unrepresentative and unaccountable. The tobacco industry comprises identifiable, legal, accountable, commercial organizations."

I was so outraged, I resigned my job in clinical medicine and, from that moment on, worked full time in tobacco control, at a critical time when Big Tobacco was looking to Asia as their future, and believed that the Marlboro horse could ride on, unchallenged.

In 1987, I became the first executive director of the Hong Kong Council on Smoking and Health, but then I stepped down and created my own role as an ambassador for tobacco control throughout Asia.

I was old enough to be taken seriously. As a female, I was seen as less-threatening. I was viewed as someone who knew Asia yet had the independence of not belonging to one Asian country, making it easier for governments to invite me to advise them.

I am no longer a lone campaigner in Asia. Tobacco control has become mainstream public health, boosted by grants from Bloomberg Philanthropies, which funds my current position at World Lung Foundation in low- and middle-income countries. And I worked for almost 25 years for no pay.

China is the largest grower and consumer of tobacco in the world, and one in every three cigarettes smoked today is smoked in China. More than a million people die from smoking annually. However much the country makes from tobacco taxes, the overall effect on the economy is negative.

The Western Pacific remains the only World Health Organization region where every country has ratified the WHO Framework Convention on Tobacco Control (WHO FCTC). But China has not yet significantly reduced the numbers of smokers, unlike many jurisdictions in Asia.

Recent signs are hopeful, though, with a substantive tome on tobacco published by the Central Party School, a directive on tobacco from the State Council, and the current drafting of a national smoke-free law.

The author has worked in tobacco control since 1984. She has published more than 200 papers, addressed over 450 conferences, and authored or co-authored 10 books. Time magazine selected her as one of the 2007 "100 most influential people who shape our world".

(HK Edition 05/20/2014 page9)