The Taiwanese authorities began formulating their policy toward the People’s Republic of China (PRC) around 1950, following the retreat of Chiang Kai-shek (蒋介石) and the KMT to the island of Taiwan after losing the Chinese Civil War to the Communist Party of China (CPC) led by Mao Zedong (毛泽东). The outbreak of the Korean War in June 1950, in particular, played a critical role in shaping what later became known as the “Taiwan question.” Historically rooted in the legacy of civil conflict, Taipei’s mainland policy has evolved over seventy-six years (1949–2025) through three major phases: the authoritarian era under one-party KMT rule (1949–2000), the democratically alternative periods marked by contrasting strategies under the Chen Shui-bian and Ma Ying-jeou authorities (2000–2016), and the more assertive and internationally engaged era under the DPP leadership beginning with Tsai Ing-wen (2016–2024) and continuing under Lai Ching-te (2024–). Each phase reflects the prevailing domestic priorities and external constraints of its time. This chapter briefly reviews Taiwan’s evolving cross-Strait policy since the Korean War in chronological order by highlighting some critical historic events and their impact on Taipei’s mainland policy making in the future.