A unique humanitarian, scientific, and technical experiment is currently taking place in a forgotten mountainous region of West Africa. The experiment is on the verge of reaching its operational stage, which consists of the eradication of a new natural hazard; one that is potentially devastating, but which has been known for only 20 years. The Lake Nyos catastrophe, which claimed 1800 victims in August 1986, was not unprecedented. Indeed, two years previously, a lethal gas burst, originating from nearby Lake Monoun in the same remote area of Cameroon, killed 37 people-an odd and tragic episode that went almost unnoticed. One had never before heard of Mother Nature asphyxiating human beings and most higher animals on such a scale in a single and brief non-volcanic event.