Literature concerning constitutional choice usually fails to distinguish between the genesis and function of an institution. As a result, the question of how constitutional systems are initially chosen is usually ignored. This gap generates a situation where, while parliamentarianism is preferred by most scholars, presidentialism is chosen more frequently by newly democratized nations. This paper is an attempt to bridge this gap by looking into the experience of Taiwan from 1986 to 1996. In general, the constitutional choice in Taiwan can be explained by the focus of the agenda-a popularly-elected presidency. After the fourth stage of constitutional reform in 1997, the ROC system has come to resemble more and more, in Shugart and Carey’s terms, the premier-parliamentary system. Several findings can be reported: (1) The issue of a popularly-elected presidency was built as a ‘focal point” in the process through the establishment of three political pacts among rivals. The participants ‘pact-building efforts were all based on considerations of advancing partisan interests by exploiting President Lee Teng-hui’s inherited strongman position. (2) The focal point was enforced by the idea of popular sovereignty, which was a tacit agreement among all rivals though with different interpretations. Under the agreement, people gradually coordinated their opinions toward favoring a directly-elected presidency. (3) The focal point helped to coordinate actions and stabilize the reform process, but has not guaranteed the stable functioning of the system because of the possibility of divided government or cohabitation in the future.