Advances in the treatment of drinking water and wastewater at fixed installations and at forward operating bases (FOBs) can significantly reduce operational costs and improve mission performance. The DoD provides drinking water to 3.4 million people living and working on DoD installations and operates more than 100 domestic wastewater facilities. Conventional treatment plants that treat drinking water and wastewater are energy intensive and critical to the operation of the installation. For deployed forces and expeditionary success, water is paramount. One of the largest shipments of supplies to the tactical edge is the delivery of water. Supplying FOBs with water and removing wastewater are both significant challenges, but they also represent significant opportunities to tackle a primary obstacle to more effective and sustainable FOBs. SERDP and ESTCP are developing innovative technologies to improve the treatment of wastewater and drinking water and maximize the potential for reuse at both fixed installations and FOBs.