On 2 and 3 April 2007, the WHO Western Pacific Regional Office hosted the first-ever rapid containment emergency exercise, an attempt to stop an influenza virus with pandemic potential. The main goal of the exercise was to determine the validity of protocols and procedures that had been developed in the Asia Pacific Region to rapidly deploy resources in an effort to contain a new, highly contagious influenza virus. The exercise also provided an opportunity to discover areas for improvement in controlling communicable disease outbreaks.