This chapter evaluates the outcomes of the Kyoto Protocol and Paris Agreement in global emission reduction and pathway design. The study shows that the Kyoto Protocol’s “top-down” mechanism reduced emissions in some countries, yet its misaligned targets (e.g., Australia) limited overall effectiveness. The Paris Agreement’s “bottom-up” NDC approach faces challenges, as current commitments meet only one-third of the 2 °C target’s requirements, with major emitters (China, the United States, India) contributing inadequately. Simulations using the C3IAM model reveal that under current NDCs, global emissions will reach 50.5 billion tons of CO₂ equivalent by 2030, leaving gaps of 12.9–18.1 and 29–34 billion tons for the 2 °C and 1.5 °C targets, respectively. A “self-preservation strategy” is proposed, requiring enhanced efforts through technological advancement and upfront investments. Results indicate an additional 19–30 billion tons of CO₂ equivalent must be reduced by 2030, with all nations achieving cumulative net benefits by 2100 (0.46–5.24% of GDP). The study emphasizes the need for developed countries to lead in net-negative emissions and support vulnerable nations through international cooperation, alongside dynamic NDC upgrades.