Whether in the coral reefs of the South Pacific, in native grasslands of the western U.S., in Brazil's Pantanal wetlands, in the hardwood hammocks of the Florida Keys, in coastal and tropical forests in the Caribbean, or across Mexican deserts, invasive species have been identified as one of the most serious and pervasive threats across all of The Nature Conservancy's Conservation Areas, threatening all our conservation accomplishments to date. Invasive species have been identified as one of the top two threats to global biodiversity, and this threat has economic consequences -estimated at $137 billion annually in the U.S. alone. In the long term, conservation success will depend greatly on the ability to prevent new invasions, and to manage "invaded" native systems for maximum benefit to native biodiversity and intact, functioning ecosystems. The prevention and early detection of new invasive species is not only important to natural systems, but can also save millions of dollars in control measures for agricultural systems. The Conservancy is actively promoting the implementation and scientific improvement of new prevention programs and methods, through capacity building and through the influence on policy. The steps for a comprehensive strategy include assessment and risk analysis, prevention, early detection, rapid response and eradication, control and management, restoration, and public education and awareness. The foundation for all these steps is science but much more is needed and our ability to incorporate new information into management decisions in a timely fashion continues to be limited.