The promotion of sustainable lifestyles ought to be seen from the perspective of consumption and production systems and life-cycle approaches that include resource extraction, manufacturing and processing, use by consumers, and disposal. Mainstream frameworks on sustainable consumption and production, including SDG 12, fail to capture downstream segments of resource consumption and production systems especially when it comes to lifestyle choices. This Policy Brief uses a composite index and indices on consumption developed by The Energy and Resources Institute (TERI) in India, to assess the state of lifestyles and consumption in G20 countries and the European Union (EU); these consumption sectors include food, transport, and residential and waste management. The G20 can play a crucial role in promoting norms on sustainable lifestyles as well as informing actions by the use of evidence and exchange of good practices. This Policy Brief recommends the establishment of a ‘lifestyles for environment metrics’ initiative, and for the G20 to launch a global partnership for sustainable lifestyles.