In today's global environment, every country confronts similar challenges in keeping its population healthy and preventing the cross-border spread of disease. SARS demonstrated this dramatically in 2003, and the ongoing challenges posed by avian infl uenza have focused attention on the need for global pandemic infl uenza preparedness. Polio has reemerged in countries that had virtually eradicated it, while HIV/AIDS and other diseases continue to threaten the stability of communities around the world. Recent examples of emerging and reemerging diseases of global signifi cance are the resurgence of dengue in tropical and subtropical areas of the world; the spread and establishment of Japanese encephalitis and West Nile viruses in new habitats and environments; and the reoccurrence and spread of chikungunya virus in India, East Africa, and several Indian Ocean islands (19, 20) . As life expectancy increases worldwide, issues related to noncommunicable conditions are also becoming increasingly common to all. By working within the collaborative framework provided by IHR (2005), countries can benefi t through improved national and international surveillance; improved systems for rapid detection of and response to public health emergencies; standardized rules for evaluation, control, and resolution of urgent events; and mechanisms to increase national and local public health security.