This research explores effective and efficient financing for adaptation through analyzing the effectiveness and performance of financing systems for adaptation using the case example of Vietnam, which is vulnerable to climate change. In particular, the Global Environment Facility (GEF) and the Bilateral Official Development Assistance (ODA) financing systems are explored. This research shows that in Vietnam, the Bilateral ODA financing systems that finance national and provincial actors are more effective than other financing systems (the Bilateral ODA financing systems that finance local actors, and the GEF financing systems). The needs of adaptation, high ability to access funds and implement adaptation, centralized as well as top-down governance systems, and strong relationships with bilateral aid agencies in Vietnam are considered to affect the evaluation of the financing systems.