Common but Differentiated Responsibilities and Respective Capabilities (CBDR–RC) is a principle in the UN Framework Convention on Climate Change that recognizes countries have different abilities and responsibilities to address climate change. The principle was established in the 1992 UNFCCC treaty and divides countries into Annex I (developed) and non-Annex I (developing) groups, with Annex I countries taking on a greater reduction role. However, debates have emerged over this division as some developing countries' emissions and capabilities have grown. While CBDR-RC remains important, later agreements have moved toward a more bottom-up approach where countries determine their own commitments according to their conditions and capabilities.