Building on the United Nations Framework Convention on Climate Change (UNFCCC), the Kyoto Protocol was the first legally binding international treaty aimed at reducing greenhouse gas emissions. Adopted in Kyoto, Japan, in 1997 and enforced in 2005, the protocol set specific emission reduction targets for developed countries. These targets represented a significant step in global climate action by holding industrialized nations accountable for their contributions to climate change. The protocol emphasized the principle of "common but differentiated responsibilities," acknowledging that while all nations are responsible for addressing climate change, developed nations bear a greater burden due to their historical emissions.