This paper focusses on the issue of floods that are transboundary and affects two countries – the plains of Nepal (Terai) and the state of Bihar in Eastern India. The paper documents the challenges faced by people in these two regions and outlines actions that may help in saving the lives and livelihood of millions of people affected by floods every year. The paper is based on dialogue and literature (the novelty of the paper) and divided into five sections. Section one provides the introduction. Section two focuses on the transboundary challenges for flood management in the Koshi Basin and Gandak Basin, examining different aspects including upstream and downstream linkages, flood typologies and the myths that have been perpetuated. Section three explores the different facets of the transboundary collaboration for flood management including a brief look at the treaties between India and Nepal, transboundary early warning systems and the global frameworks. Section four puts forth ways for enhancing transboundary river basin management and benefits that could be derived from co-management of the river systems across political boundaries. Finally, Section five provides the conclusions of the study.