This chapter explores the origins and consequences of national security institutions in the People’s Republic of China during the tenure of Mao Zedong. It first explains the political logic behind Mao’s choice to shift from integrated to fragmented institutions: Mao chose to weaken the bureaucracy to ensure a stable political succession after his death. It then presents a medium-n analysis to show how this shift from integrated to fragmented institutions degraded China’s crisis performance. Detailed process tracing of two cases illustrates how different institutional designs shaped crisis performance through poor bureaucratic information provision at the onset of each crisis. Prior to the 1962 Taiwan Strait Crisis, Mao’s decision-making benefitted from high-quality bureaucratic information that comparatively inclusive and open institutions afforded. By the onset of the 1969 Sino-Soviet Border conflict, however, Mao was forced to make decisions based on incomplete and biased information provided by bureaucrats who feared Mao’s retribution. The chapter thus illustrates how institutional changes can dramatically change the quality of information upon which the same leader bases their choice of conflict.