In this case study, we investigate the applicability of rainwater harvesting as a sustainable water supply option in Banda Aceh, Indonesia, an area severely hit by the tsunami in 2004. Due to technical and geographical factors, the local residents spend approximately 16% of their incomes on the purchase of water. For this reason, a new, economical, and sustainable way of obtaining water is a most important and urgent concern. A team from Seoul National University recently developed and installed several rainwater harvesting systems in the area in January 2007 and 2008, focusing particularly on increasing public awareness of rainwater harvesting and capacity building in Banda Aceh. This paper discusses the general public perceptions, installation methods, and viability of the system. We found that rainwater harvesting, accompanied by an increase in public awareness and appropriate education, can best serve the needs of the community.