The Zambezi River basin is the fourth largest in Africa. Covering an area of about 1 400 000 km2 that is shared among 8 countries, it is the home of over 30 million people. There are ample opportunities for development in the region, including on the hydropower sector, whose estimated potential still to be exploited amounts to over 8 000 MW. In the future, the Zambezi is thought to be particularly vulnerable to climatic changes, with sizable expected impacts on average runoff, and will play a key role in the challenges posed by regional water scarcity. How future and current hydropower schemes are laid out and operate will affect the valuable ecosystems still thriving in the riparian areas of the basin and impact economic, as well as societal aspects. The present contribution employs a daily flow routing model in order to evaluate the impacts of different future hydropower development scenarios on the Zambezi River basin. Resorting to it and a multi-objective optimization technique the trade-offs between environmental and hydropower production concerns were clearly identified.