This book, entitled "Hydro-agricultural developments: Diagnosis and assessment of environmental risks in Benin", is a participatory action research project under the "Environment and Climate Change" programme of the Centre d'Actions pour la S�curit� Alimentaire et le D�veloppement Durable (CASAD-Benin). It provides a better understanding of the characteristics of hydro-agricultural developments and the associated environmental risks. After identifying the different types of hydro-agricultural development (hydro-agricultural development using gravity, pumping and manual watering), the sources of environmental risks associated with their development were identified and analysed. The results show that the various practices have led to degradation of the plant cover, causing it to decline and reducing soil fertility. The book proposes sustainable management measures to reduce the environmental risks of hydro-agricultural development.