Attributional and Consequential Modelling

Two ways of building a life cycle model, suited to different questions. An attributional model describes the share of the world’s impacts that belongs to a product, using average data. A consequential model describes how impacts change as a result of a decision, using the suppliers and technologies that would actually respond to it. “What is the footprint of this reclaimed water?” is an attributional question; “what happens if this city switches to reuse?” is a consequential one.