Integrated Waste Management is one of the holistic approaches to environmental and resource management which are emerging from applying the concept of sustainable development. Assessment of waste management options requires application of Life Cycle Assessment (LCA). This paper summarizes the methodology for applying LCA to Integrated Waste Management of Municipal Solid Waste (MSW) developed for and now used by the UK Environment Agency, including recent developments in international fora. Particular attention is devoted to system definition leading to rational and clear compilation of the Life Cycle Inventory, with appropriate 'credit' for recovering materials and/or energy from the waste. LCA of waste management is best seen as a way of structuring information to help decision processes.