S. Nazrul Islam, Chief of Development Research of the United Nations, received his Ph. D. in economics from Harvard University and Masters from Moscow State University. He also studied economics at Dhaka University. During his long teaching career, Islam taught economics at Dhaka University, Harvard University, Emory University, Kyushu University, and St. Johns University. Islam made his mark on research in several areas of economics, including growth, transition, development, and environment. He has published twenty books and numerous articles in reputed international journals. In recent years, Islam devoted more of his research to issues of the environment, including rivers. He developed a novel conceptual framework for discussion of river policies and has applied it to analyzing water development experiences across the world and put forward an alternative water development strategy for Bangladesh. His recent books on river issues include Let the Delta Be a Delta (2016); Rivers and Sustainable Development (2020); and Water Development in Bangladesh: Past Present & Future (2022). Islam is the founder of the Bangladesh Environment Network (BEN) and the initiator of the Bangladesh Poribesh Andolon (BAPA). Through these organizations, he is striving to bring about policy changes necessary for the protection of the rivers and the environment.