The document discusses the ecological footprint and the EU Emissions Trading System (ETS). The ecological footprint was developed in the mid-1990s and measures the strain placed on natural resources and ecosystems. It is calculated by comparing the resources consumed by an individual to the world's population and expressing this as a ratio. The ETS is the EU's cap-and-trade system for limiting greenhouse gas emissions. Facilities have a limited allowance that can be traded, and international credits from emission reduction projects can be purchased, allowing flexibility in reducing emissions at lowest cost. The EU has set goals to reduce emissions by 20%, 40%, and 80% by 2030, 2040, and 2050 respectively.