Is it sci-fi-film–style panic, or are we truly running out of water? Jay Famiglietti and Peter H. Gleick, two scientists who have done more to bring attention to the consequences of our mismanagement of water than anyone, divulge the data. Wired magazine designated Gleick “one of 15 people the next President should listen to” in 2008, while Famiglietti's innovative use of satellites to assess groundwater supplies was recently highlighted on 60 Minutes. Mark Gold, UCLA associate vice chancellor for environment and sustainability, moderates.