This article attempts to explain the formation of Taiwan’s opposition coalition, a phenomenon of critical importance to the unfolding of her democratic politics. Seeing the case as a multi-stage coalition formation game, the analysis shows that an electoral alliance between the opposition parties can be engineered regardless of how they interact in the legislature-as long as the cohesion of their legislative partnership is based on the expectation that they will cooperate in the upcoming presidential election. Another main argument is that the key to a successful opposition alliance in the 2004 presidential election hinges on the ability to produce a profile of divisible goods for the election. Once ready, these goods must be allocated in proportion to the electoral strength of each party. The greatest obstacle for the pan-Blue parties to build a joint campaign team may lie in the fact that the People First Party (PFP) has a better chance to deliver a viable candidate; the party is weaker however than the Kuomintang (KMT) in organizational and financial resources.