How important is sanitation during a humanitarian crisis? Why is it important to explore ecologicaland sustainable sanitation? This article looks at the case of Eastern Chad, an example of a majorlong-term crisis. From an acute emergency in 2003, the crisis has gone through a number ofphases. The appropriateness of aid mechanisms is currently being questioned, with a particularfocus on sanitation. Sustainable sanitation can help to improve the quality of life of refugees andIDPs as well as local populations. From this perspective, what lessons from Eastern Chad could beuseful in other contexts?