The sustainability of a single activity, production process or product

When is a specific activity, production process or final product sustainable? Life Cycle Assessment and Environmental Footprint Assessment are two different methods to analyse natural resources use and emissions along product supply chains. It is argued that the two methods fundamentally differ in the way they address the question of product sustainability. Whereas the former method takes a comparative approach, comparing potential environmental impacts of alternative products, thus avoiding the question of sustainability at systems level, the latter method takes a holistic systems approach but has difficulty to attribute overall unsustainability to single processes or products. Both methods are useful, for different purposes, and complementary. It remains a challenge to develop a consistent and coherent theoretical framework providing an umbrella for the two different methods.