The relations between international trade and energy are becoming more complex. During the last decades, the number of fully operational free trade agreements increased from 22 to 305 between 1990 and 2020, reducing the impact of the World Trade Organization and global trade multilateralism. Free trade agreements have begun to include climate action based on instruments like carbon-based measures or technical standards. This entry identifies some of the most important tools contributing to reinforcing the trade–climate–energy nexus.