This dissertation proposes a unified account of the syntax of valence in Javanese which includes applicative, passive and adversative passive. The three valence-changing processes have been commonly analyzed as separate phenomena in the previous frameworks. The dissertation shows that independent analyses on the syntax of valence by Baker (1988), Marantz (1993), and Pylkkänen (2002) on applicative, Kratzer (1996) and Collins (2005) on passive, and Kubo (1992) and Pylkkänen (2000) on adversative passive are problematic for Javanese. First, the frameworks cannot provide sufficient argument heads for all of the three functions of suffix -ake: benefactive, instrumental, and theme. Second, they cannot explain the three positions of the passive agent: preverbal, postverbal and in a PP at the end of sentence. Third, they cannot explain the fact that Javanese adversative passive has no possessor raising construction. I propose that the problems can be solved with a unified account of the syntax of valence of Javanese. This is done by incorporating the frameworks of Bowers (2010) on applicative and passive, Merchant (2013) on passive, and Aldridge (2011) on ergativity. Based on Bowers (2010), the three functions of suffix -ake can be accommodated at separate argument heads. Moreover, based on the same framework, the agent can be originated at the agent head at the bottom of the derivation, and then raised to the preverbal and the postverbal positions due to the ergative features at the positions. Lastly, the adversative passive is defined as a combination of passivization with a specific adversative passive ke- merged at the Spec of Voice and the applicative suffix -an merged at the Affectee head.