Microsoft founder Bill Gates and New York Mayor Michael Bloomberg have pledged $500 million to fight the growing tobacco epidemic in developing countries. The investment will help governments implement proven programs and policies for reducing tobacco use. The announcement came at a press briefing in New York City on July 23.

The World Health Organization (WHO) has established MPOWER, a package it describes as the six most important and effective tobacco control efforts: monitor tobacco use and prevention policies; protect people from tobacco smoke; offer help to quit tobacco use; warn about the dangers of tobacco; enforce bans on tobacco advertising, promotion, and sponsorship; and raise taxes on tobacco.

The strategies are "a rigorous approach to stopping the tobacco epidemic," according to Mr. Bloomberg, whose foundation supported their development. However, despite strong evidence of effectiveness and public support, only about one in five countries has fully implemented any of the five key policies, and no country has fully implemented all six.

The billionaire philanthropists hope that will soon change. Mr. Bloomberg has pledged an additional $250 million over 4 years, on top of a $125 million-commitment made in 2005. The Bill and Melinda Gates Foundation will invest $125 million over 5 years, including a $24 million grant to the Bloomberg Initiative.

"Our commitments will help governments confront the tobacco epidemic by implementing the proven MPOWER package," said Mr. Bloomberg in a statement. "This means [ensuring] well-staffed tobacco control programs, raising tobacco taxes, running hard-hitting public information campaigns, creating comprehensive smoke-free public places, and banning tobacco advertising."

There are one billion smokers in the world. In recent years, the epidemic of tobacco use has shifted from high-income nations, where tobacco use is generally decreasing, to low- and middle-income nations. By 2030, global tobacco deaths will reach 8 million per year, with 80 percent occurring in developing nations. WHO warns that unless urgent action is taken, more than one billion people could be killed by tobacco during the 21st century.

The Bill and Melinda Gates Foundation funds will be used to build economic evidence to support tobacco control and to educate the public about the harmful effects of tobacco. Gates Foundation funds will also support efforts to prevent the epidemic from taking hold in sub-Saharan Africa, where smoking rates have traditionally been low.

"Tobacco-caused diseases have emerged as one of the greatest health challenges facing developing countries," said Mr. Gates in a press release. "The good news is we know what it takes to save millions of lives, and where efforts exist, they are working." Tobacco control is a new focus for the Gates Foundation, but the organization has considerable experience working with governments and civic organizations on diseases such as malaria.

In their announcement, both Mr. Bloomberg and Mr. Gates called on government and business leaders to make the fight against tobacco a higher priority by increasing resources for tobacco control and implementing proven policies to reduce tobacco use.