INTRODUCTION: Perspectives on water and land in the Sahel: facing polycrisis 1: Setting the scene. Unfulfilled futures. One hundred years of large-scale irrigation projects in the Sahel PART I: Contextual issues 2: Environmental crisis narratives in the Sahel and the solutions they call for: The case of Lake Chad 3: Layered crises: climate change, water insecurity and irrigation in the Sahel 4: The “glocal” nature of jihadist insurgencies? Conflict, space, land, and resources in the Sahel PART II: Cartographic sketches of the Sahel 5: Defining the Sahel. B-ordering an area study 6: Land degradation and the Convergence of Evidence in the Sahel 7: Troubled waters 8: Shapes of the water: the rectangle and the circle. A tentative survey on irrigation in the Sahel 9: Interlude. The Sahel in historical atlases (1493–1789) Interlude: Sahel in historical cartography PART III: Complicated muddles of water and land 10: Sudan: a 'picture' of irrigation spaces before April 15th 2023 11: Traces of irrigation: Some recent developments in the Chadian region 12: The production of land insecurity and conflict in the Sourou valley (Burkina Faso) PART IV: Connections, rights and conflicts 13: Land and water rights in the Niger Inner Delta: between negotiation and conflict 14: Ségou(s), the Niger and the other side of the river: how water tells the city in the Sahel 15: Changing patterns of resource conflicts in the Logone floodplains (Cameroon/Chad). Between actors’ practices and development narratives PART V: Towards a fluid research agenda 16: COVID-19, polycrisis and metamorphosis: A reflection on doing collaborative research in, on and with the Sahel 17: Ways of being-knowing and doing with water and land in Africa