SCIENCE sciencemag.org P H O T O : D A N M U L L E N / F L IC K R worldwide to create the attendant monitoring programs that measure the successes of these changes, warn about and characterize impending system failures, and allow us to learn how to manage diminished pollination capacity. Food security will require this expertise. Bees are not optional. David Inouye,* Samuel Droege, Jonathan Mawdsley Rocky Mountain Biological Laboratory, Crested Butte, CO 81224, USA. University of Maryland, College Park, MD 20742, USA. Upper Marlboro, MD 20774, USA. Association of Fish and Wildlife Agencies, Washington, DC 20002, USA.