The full novelty of COVID-19 has posed unprecedented challenges to the whole world, and China’s response at the stage when Wuhan city was the epicenter has performed the effective transition from cognition to collective action. Scientific expert groups played a decisive role in recognizing the novelty of COVID-19, and unified coordination under China’s Central Leadership Group facilitated the organization of collective action. Vertically, the Central Instruction Group to Hubei Province utilized both coordination capacity at the central level and situational awareness at local levels. Horizontally, paired assistance programs provided strong support of professional medical personnel and materials from 19 provinces to 16 cities besides Wuhan in Hubei Province and significantly alleviated the situation. The State Council Joint Prevention and Control Mechanism built effective networks led by the National Health Commission and strongly improved interagency collaboration. These new structures supported the operation of complex adaptive systems for emergency management in China’s centralized administrative context.