This paper overviews the main work and achievements of the International Energy Agency's Task on Municipal Solid Waste (MSW) conversion to energy. The objectives of the Task were to encourage information exchange between research and development programmes and other new initiatives relating to energy recovery from MSW, and to use this information to benefit research, development and deployment programmes on energy recovery from MSW in participating countries. Governments are now encouraging the sustainable use of MSW resources, both domestically and as part of their international obligations. These encourage development of a waste management hierarchy which places greater emphasis on waste prevention and minimisation through materials and energy recovery. The IEA Task provided participating countries with an international perspective in the areas of thermal technologies (incineration of MSW and refuse derived fuel and ash residues), biological technologies (landfill gas and anaerobic digestion of MSW) and generic issues relating to MSW conversion technologies (source separation, recycling, mechanical processing, sampling and analytical protocols). Work was carried out through meetings, study tours and networks. The main benefits from this international collaboration were that participants obtained up-to-date information on technical and nontechnical issues affecting energy from waste technologies, including legislation, methodologies, and plant experience, that they could then use to encourage the development of energy from waste in their own countries. The work of the Task will continue for a further three years during 1995-97.