Three days before Christmas, Francisco (Chico) Mendes was shot dead in the small Amazonian frontier town of Xapuri in Brazil. He was killed by hired assassins because of a land dispute. But he died for a cause that may be one of the last, best hopes for preserving the Amazon rain forest and with it the livelihoods of a million and a half rubber tappers and "extractivists." Mendes labored to organize "extractive reserves" where rubber tappers like himself could continue to harvest the forest without having it burned and bulldozed for cattle ranches and farms. He had helped organize about 500 families into Brazil's first rubber tappers' union and succeeded in establishing the first pilot reserves. From this modest beginning, extractive reserves was an idea that was taking root throughout the Amazon, largely through Chico's efforts. Mendes, a stocky man with thick, calloused hands, had spent most of his life in the Amazon rain forest tapping rubber. He supported himself and his family by harvesting latex and, occasionally, indigenous fruits and Brazil nuts. Throughout the region one finds these families, often living in isolated clearings and along estuaries. They are by and large uneducated, poor, constantly in debt and at the mercy of local middlemen, merchants and land speculators. Until recently the Brazilian government ignored their existence. In the late 19th century immigrants from the northeast and south flooded into the Amazon, attracted by the rubber boom. At the time, the Brazilian seringa or rubber tree, which grows wild in the rain forest, was the world's unique source of rubber. However, seeds smuggled from Brazil in 1876 by the British eventually gave rise to plantations in Ceylon (now Sri Lanka) and the Malay Peninsula, and in a matter of decades these new sources had supplanted Brazil in the world market, and the region plunged into recession. Despite a brief resurgence of the rubber industry during World War II, Brazilian latex fell once again on hard times with the development of synthetics, and most of the seringueiros left the forests. Chico was one of the 80,000 rubber tappers who still remain. Mary Allegretti, a Brazilian anthropologist and one of the forces behind the "extractive reserves" movement, "discovered" Chico and the seringueiros in the early 1980s. During this period, she and Chico developed the concept of the extractive reserves, the vehicle by which the seringueiros could establish legal claim to the lands they inhabited. The reserves would be economically viable, and the seringueiros themselves, organized and ever present, would keep trespassers out. In the process the unions would provide a focus for cooperative efforts in education, health and marketing. Vast tracts of virgin forest would be preserved. Chico Mendes emerged as the tough, charismatic and effective leader of the growing movement. One of his finest moments was in 1985 when he lead 150 seringueiros in a march on Brazil's capitol, Brasilia. The participants had to be gathered from their scattered dwellings, organized and transported 1,000 miles to Brasilia. Many had never been in a city before. For the first time in their history, the seringueiros were organizing to save their forest. But Mendes' successes threatened landowners. The Amazon is Brazil's version of the American wild west, and land wars are endemic. Hundreds of poor squatters have been murdered in recent years by hired guns generally in the pay of the large landowners. Few of the killers are ever brought to justice. The week before he died, Mary Allegretti spoke to me of her wish to provide Mendes with better security; at the time he was shot he was accompanied by two bodyguards provided by the state. I was with Chico last November. He had already visited neighboring states and was optimistic that the extractivist reserves idea would mobilize seringueiros throughout the Amazon region. The Brazilian government's endorsement of the idea was a critical step forward. Now he is dead. However, it seems as though the national and international outcry against this atrocity points to increased environmental concern. The accused murderers, two brothers, have been jailed. Others are being apprehended. It is possible that a high-ranking official may also be implicated. Perhaps it is consolation that his supporters both in Brazil and abroad are already joining forces to form the Chico Mendes Foundation for the continuance of his work. His enduring legacies are the rubber tappers' union, the extractive reserves and the hope he gave us for the rain forest. The writer is director of Latin American programs for Ashoka, a nonprofit international development organization.