Long-term planetary sustainability requires policy and technological interventions across energy systems to bring about choice of fuels, the way they are produced and consumed, and the way in which resources are affected systemically at every stage of the energy system (established but incomplete). {17.5.1, 17.5.2} Mechanisms to address these challenges include carbon pricing (cap and trade systems, carbon taxes and other economic instruments such as fuel taxes and different subsidies to renewable energy), regulatory approaches (energy efficiency standards, command-and-control, mandatory decommissioning of old plants), information programmes (addressing behaviour, lifestyle and culture), and addressing administrative or political barriers (including through international cooperation) (established but incomplete). {17.5.3} Decarbonizing supply and improving demand efficiency are two key policy elements that have been applied successfully (well established). Nevertheless, they need to be scaled up rapidly, together with the phasing in of new policies. {17.5.4} The global economy currently operates predominantly in a linear mode whereby resources are extracted, converted through manufacturing to products and then disposed of (well established). {17.6.1} The use of natural resources has grown rapidly over the last two decades and the global supply chains of resources have become more complex, resulting in growing environmental pressures and impacts (well established). {17.6.1} A global shift is needed to a circular economy in which resource efficiency contributes to economic growth and human well-being, with reduced environmental pressures and impacts (established but incomplete). This would have substantial co-benefits for greenhouse gas abatement and waste and pollution minimization. {17.6.2} A circular economy is a systems approach to industrial processes and economic activity that enables resource to maintain their highest value for as long as possible (well established). Key considerations in implementing a circular economy are reducing and rethinking resource use, and the pursuit of longevity, renewability, reusability, reparability, replaceability and upgradability for resources and products that are used. Resource efficiency contributes to economic resilience by increasing the supply security of primary materials and closing of resource loops through remanufacturing and recycling, thereby reducing the pressures of resource exploitation, climate change, accumulation of toxic substances in ecosystems, and biodiversity loss (well established). {17.6.2} Resource efficiency does not always happen spontaneously but requires well-designed policies that facilitate a change to sustainable systems of production and consumption and sustainable infrastructure (established but incomplete). {17.6.4} The physical, social, economic and health impacts of climate change, especially on the most vulnerable communities, require urgent adaptation approaches that are systemic, multidimensional and transformative (established but in...