As China's economic growth and military modernization continue, analysts are paying increasing attention to Chinese security policy. Two shortcomings, however, have become apparent in their analyses. First, contending schools of thought tend to hold that the conceptual foundation of Chinese policy is constant and static over time. The second shortcoming has to do with the debate on whether China is a revisionist or a status quo power. This chapter attempts to correct these two shortcomings by addressing two research questions. It makes two arguments. First, the Chinese conception of security and security approaches under Mao was mainly driven by the concern for subnational and transnational class-based security and struggle. Second, major domestic changes, such as leadership changes and the consolidation of a new leadership, bureaucratic bargaining, the need to create a secure external environment for domestic economic development, and changes in the economy and military capabilities, account for major changes in the Chinese conception of security and security approaches.