California’s growing communities and industries require an adequate supply of clean water to thrive into the future. This report suggests that action is immediately needed to reduce the growing tensions over California’s water resources and to address the state’s persistent water supply challenges. The authors’ recommendations would annually save a million acre-feet of water quickly and at a lower economic and ecological cost than that of developing new supplies (an acre-foot is equal to the volume of a sheet of water one acre in area and one foot in depth).