This article reviews the implementation of climate mitigation targets set at the 2009 Copenhagen Conference (COP15) and assesses the effectiveness of national efforts to meet these targets. It analyzes CO₂ emissions from both territorial and consumption-based perspectives, revealing that 12 out of 34 analyzed countries failed to meet their targets, while 7 achieved them through domestic efforts, albeit with carbon leakage through international trade. Key factors in meeting targets included energy intensity reduction and improvements in the energy mix. However, many countries' efforts fell short of their latest nationally determined contributions (NDCs). The study highlights the importance of tracking and reviewing mitigation efforts to meet the Paris Agreement targets. Climate change poses a significant challenge to society, with global greenhouse gas emissions in 2019 being 1.54 times higher than in 1990. Countries are urged to act on the principle of 'common but differentiated responsibilities' to address climate change. The COP15 conference laid the groundwork for subsequent climate agreements, including the Paris Agreement. However, the implementation of Copenhagen targets has been inconsistent, with some countries achieving their goals through domestic efforts and others relying on outsourcing, leading to carbon leakage. The study also examines the factors influencing changes in emissions, such as energy intensity, GDP per capita, and industrial structure. It finds that energy intensity and the share of coal were significant contributors to emissions reduction, while the share of oil and natural gas had less impact. The analysis shows that countries that achieved their targets did so through improvements in energy efficiency and structural changes, while those that failed to meet their targets struggled with economic growth and emission reduction. The article emphasizes the need for continued efforts to meet NDCs and to address the challenges of economic growth and emission reduction. It calls for stronger policy support to adjust energy and industrial structures to further reduce emissions. The study also highlights the importance of consumption-based emissions in climate negotiations, as they provide a more equitable framework for national responsibilities. Overall, the findings underscore the need for timely tracking and review of mitigation efforts to achieve global climate goals.This article reviews the implementation of climate mitigation targets set at the 2009 Copenhagen Conference (COP15) and assesses the effectiveness of national efforts to meet these targets. It analyzes CO₂ emissions from both territorial and consumption-based perspectives, revealing that 12 out of 34 analyzed countries failed to meet their targets, while 7 achieved them through domestic efforts, albeit with carbon leakage through international trade. Key factors in meeting targets included energy intensity reduction and improvements in the energy mix. However, many countries' efforts fell short of their latest nationally determined contributions (NDCs). The study highlights the importance of tracking and reviewing mitigation efforts to meet the Paris Agreement targets. Climate change poses a significant challenge to society, with global greenhouse gas emissions in 2019 being 1.54 times higher than in 1990. Countries are urged to act on the principle of 'common but differentiated responsibilities' to address climate change. The COP15 conference laid the groundwork for subsequent climate agreements, including the Paris Agreement. However, the implementation of Copenhagen targets has been inconsistent, with some countries achieving their goals through domestic efforts and others relying on outsourcing, leading to carbon leakage. The study also examines the factors influencing changes in emissions, such as energy intensity, GDP per capita, and industrial structure. It finds that energy intensity and the share of coal were significant contributors to emissions reduction, while the share of oil and natural gas had less impact. The analysis shows that countries that achieved their targets did so through improvements in energy efficiency and structural changes, while those that failed to meet their targets struggled with economic growth and emission reduction. The article emphasizes the need for continued efforts to meet NDCs and to address the challenges of economic growth and emission reduction. It calls for stronger policy support to adjust energy and industrial structures to further reduce emissions. The study also highlights the importance of consumption-based emissions in climate negotiations, as they provide a more equitable framework for national responsibilities. Overall, the findings underscore the need for timely tracking and review of mitigation efforts to achieve global climate goals.