Track II diplomacy is of specific strategic interest for Taiwan under the barriers of participation in international organizations and the formation of diplomatic ties with major powers. The Taipei-Seoul Forum/ Seoul-Taipei Forum (TSF/STF), which was inaugurated in the early 1990s worked as an important example of how track II diplomacy can contribute to Taiwan’s relations with South Korea based upon interpersonal relationships and links between think tanks on either side. This paper examines the development of TSF/STF to examine the opportunities for and constraints on track II diplomacy efforts to nurture bilateral relations between Taiwan and South Korea. Through the lens of social capital as an analytical framework, this paper portrays the unique process of interpersonal social networking that takes place through TSF/STF, which has managed to preserve a fragile bilateral relationship during a period of extreme difficulty.