This book has elucidated the updated knowledge on Tonle Sap Lake (TSL) and identified relevant knowledge gaps. In this final chapter, we carefully selected and concisely summarized the important remaining knowledge gaps and directions for lake environmental management. For most of the lake components, we stress the importance of continuous and comprehensive monitoring as a basis of science and environmental management. For further research, interdisciplinary collaboration would be the key to enrich tropical limnology and floodplain science using the fascinating field of TSL. This is because it is inevitable to integrate physical, chemical, and biological processes in our understanding to highlight mechanisms that are critically important for the management of TSL. To take such next challenges, we humbly hope that the book will serve as a reference.