Waste management in developing countries is a growing concern because of its impact on Man and on the environment. The traditional method, known as “landfilling”, is still the most widespread for solid waste disposal, because of its relatively low cost. In the developing countries, the insufficiency of financial and technical means too often causes the municipalities and the population to dump waste into uncontrolled sites. This study has been carried out within the frame program of the French Agency for Environment and Energy Management (ADEME), dealing with the landfilling of municipal waste in developing countries. The major objective is the definition of a methodology for designing and operating municipal waste landfilling facilities, suitable for developing countries. This paper presents the first results obtained on three sites, i.e. the lanfilling facility of Essaouira (Kingdom of Morocco), under mediterranean climate, the facility of Nkolfoulou, located near the city of Yaoundé (Republic of Cameroon), under equatorial climate, and the facility of Go Cat, located by Hô Chi Minh-City, in Vietnam, under wet tropical climate.