- Under the Paris Agreement, parties submitted documents outlining their commitments to climate change mitigation and adaptation, called Nationally Determined Contributions (NDCs), which are set to be updated to increase ambition by 2020. Costa Rica and México are known for their significant national actions on climate change, so comparing these two NDCs will inform the international climate regime of best practices. The two NDCs were compared on mitigation within the categories of emissions goals, land use, land use change, and forestry (LULUCF), and energy. They were compared on adaptation within adaptive capacity, climate finance, and technology transfer. Overall, Costa Rica’s emissions goals were significantly more ambitious than México’s, and its energy goals were more specific, but México had more specific LULUCF goals. Both NDCs were ambiguous regarding their adaptation goals, with Costa Rica tending to refer to separate official documents for more specific information, and México mentioning very little related to climate finance and technology transfer. Overall, Costa Rica’s current NDC is compatible with the Paris Agreement’s 2°C goal, and México’s is insufficient. Still both Costa Rica and México, as well as other nations across the globe, could improve their own NDCs using the information from this comparison.