For nearly two decades, Condé Nast Traveler has been honoring environmental visionaries around the world who have found innovative solutions to seemingly intractable problems. Each year, we receive hundreds of nominations and, with the help of our panel of expert judges, select one winner and three runners-up. This year's recipient of the Environmental Award is an impassioned Indonesian activist who is tackling one of the decade's most alarming ecological disasters—his country's rapidly disappearing forests. Thanks to his tireless commitment, there's new hope. The accomplishments of the runners-up—from safeguarding Brazil's endangered wildlife to preserving Louisiana's magnificent cypress trees—are no less inspiring. These conservation success stories go far beyond preserving some of our favorite travel destinations. Our four honorees are helping to alleviate poverty, promote social justice, and repair fragile ecosystems within their own communities. Here, we celebrate their good works and the places they're committed to protecting.

Winner: Silverius Oscar Unggul
An Indonesian environmentalist finds a formula to save his country's forests. Deborah Dunn reports

I am walking through a sun-streaked grove of teak trees in the mountains of Southeast Sulawesi, a pastoral province on Indonesia's fourth-largest island. Leading the way are two local farmers, Warma Samedi and Abdul Rahman, and the young environmentalist Silverius Oscar Unggul, who has helped them and their neighbors turn this unlikely corner of the sprawling archipelago into a small ecological triumph with epic possibilities.

As in most of rural Indonesia these days, Sulawesi's landscape is a succession of carefully tended rice fields, verdant peaks, and tracts of ravaged earth—scars of a rapacious clear-cutting industry. Within the past 25 years, the island's lowland forests have all but vanished. Kendari, the provincial capital and Unggul's hometown, fronts a sediment-lined bay. Bald spots blemish the green hills just above. "We swam here all the time as children," says Unggul as we drive past. "Now, nobody swims here."

Unggul, 37, has been keeping a watchful eye on Sulawesi's thinning tree lines since his days as an agriculture student at the university in Kendari. There, he and eight friends founded an environmental nonprofit to crusade against illegal logging and to expose the timber companies involved. But it wasn't until another friend—a farmer from a small village near Kendari—was arrested for logging in a state forest without a permit that the group realized the problem also existed at the grassroots level. "We had tried telling the villagers to stop cutting down trees, but then they'd ask, 'How will we get money? How will we feed our families?'" he recalls.

In 2002, Unggul and three of those same college friends helped launch Network for the Forest (JAUH), an organization rooted in the unconventional idea that local communities can actually turn a profit by preserving the environment. The pilot program, a teak plantation cooperative in Southeast Sulawesi, has been such a stunning success—and a financial windfall for farmers—that Indonesia's Ministry of Forestry touts it as a potential remedy for what even the government acknowledges is a nationwide environmental catastrophe.

All told, Indonesia has been losing more than four million acres of forest—an area twice the size of Yellowstone National Park—every year for the past two decades. Some 75 percent of the cutting is at the hands of illegal loggers. The island republic landed on an unenviable list last spring, when a report released by the World Bank and the British government named Indonesia the world's third-largest emitter of greenhouse gases, just behind the United States and China. Eighty percent of those carbon emissions are due to deforestation and land degradation. "Trees store carbon," explains Erik Meijaard, senior ecologist for the Nature Conservancy. "Once you cut trees down and they decompose, the carbon is released into the atmosphere."