The UK Government is aiming to increase the amount of construction and demolition waste that is reused and recycled as part of its commitment to a sustainable waste management strategy. Reusing and recycling construction waste reduces the need for raw materials and energy, with corresponding reductions in environmental emissions, aesthetic impacts and damage to natural ecosystems. However, the use of secondary materials also gives rise to environmental and social impacts, particularly in the transport and reprocessing stages. Lifecycle assessment can be used to compare alternative options for the sustainable management of construction waste. Within the assessment, economic valuations of environmental and social impacts provide weightings to enable this comparison. In the past, waste management decisions have been based primarily on financial cost, and there has been no mechanism for taking environmental and social costs and benefits into consideration. Industry and local authorities are increasingly having to take account of a broader range of criteria, and the discipline of environmental economics provides a means by which these 'external' impacts can be quantified and included in decision making alongside financial costs.