Marine nurseries are critically important subsets of the global ocean and coastal systems, supporting not only marine food webs but also providing key services for humankind.  These areas are being degraded and lost by direct conversion of land and nearshore areas through coastal development, as well as from indirect impacts of human activity on land and sea via pollution, reduction of freshwater flows, climate change, and species introductions.  To stave off the dramatic losses in nurseries that are now occurring worldwide, we must do a better job of valuing these habitats and communicating their value to the public, and we must fully address the entire spectrum of threats that impact these sites.  As our dependence on marine fisheries and marine amenities grows, we must be careful not to undermine the very systems upon which our future rests.