We're in for a litany of woe now that the World Summit on Sustainable Development has begun in Johannesburg, South Africa. But let's not fret.

Yes, those who read the Club of Rome's "Limits to Growth" report 30 years ago -- and took its projections of disease, despair, death and disaster to heart -- will enjoy an international stage like never before. Some 60,000 attendees, including 100 heads of state, will be on hand.

Let the doomsayers have their day. Let them discuss how they meant to say "global warming," not "global cooling" 30 years ago. How they meant to say we'd have too much food now, not too little -- and that what Western democracies need to do is drop farm subsidies, not send more food. Let them talk about how they meant that technology and economic growth would be a force for good, not the embodiment of evil.

Indeed, let us rejoice at how far the argument has shifted since the doomsayers' last performance in 1992 in Rio de Janeiro. Don't believe it? Consider this sentence from a New York Times story on the summit's opening day: "Environmentalists and advocates for the poor are already vowing to march through the streets by the thousands on Saturday to ensure that the link between poverty and environmental decay remains high on the agenda."

At least we've got that straight. The cleanest countries are those with the least poverty: the United States, Canada, western Europe, Australia. The dirtiest are those with the most: Haiti, India, China.

According to James Glassman of TechCentralStation.com ("Where free markets meet technology"), researchers at the World Bank have discovered a bell-curve effect with regard to the relationship between poverty and the environment. As countries' per capita income moves upward toward $5,000, pollution increases. Once per capita income tops $5,000, pollution begins to decrease rapidly.

"It makes sense for public policy to be directed toward getting nations over the $5,000 hump and onto the down slope of this curve," Glassman says. "There is a direct, close and logical correlation between economic prosperity and an improved environment."

This may seem self-evident. But the delegates to Rio never fully grasped it and thus have little to show, 10 years later, for their efforts. If delegates to Johannesburg want the work of this conference to endure, they should follow two simple rules -- make sound science the basis for all recommendations, and truly weigh the costs against the benefits of any proposal.

For instance, much will be made of the fact that the United States emits 24 percent of the world's greenhouse gases -- those said to cause global warming. Delegates will argue that if the United States truly wanted to sustain the environment -- to pass to our children a cleaner world than we lived in -- it would sign the Kyoto Accords, which call for reducing these emissions below 1990 levels.

But little will be said about how the United States also produces 24 percent of the world's gross domestic product and how all that stuff doesn't produce itself. Or about how the $400 billion estimated annual cost of Kyoto compliance would drag down not just the U.S. economy but the economies of dozens of countries that depend on America to make their own economies work.

And almost nothing will be said about how 17,000 of America's leading climatologists, meteorologists and other scientists have signed a petition saying the science supporting the global warming theory -- and thus, Kyoto -- is no more reliable than the science that, 40 years ago, predicted we'd be well into the next ice age by now.

The fact is, as Glassman says, cheap, widely available energy plays a vital role in economic growth. And right now, that means burning fossil fuels. To limit these sources without alternatives in place is to limit economic growth -- particularly in developing countries -- and to sustain poverty.

We don't need restrictions on American energy use, limits on economic activity or some utopian wealth-transfer scheme. We need what President Bush proposed earlier this year at Monterrey, Mexico -- aid to those poorer neighbors who truly undertake the pro-growth measures needed to make our investments worthwhile.

Those that open their economies to foreign investment, clean out corruption, ensure contracts will be honored and remove barriers to entry for businesses will enjoy more wealth, a better life and -- not so coincidentally -- a cleaner environment.

Charli Coon is an energy policy analyst at The Heritage Foundation, a Washington-based public policy research institute.