Vietnamese medical personnel practice chest compressions after an advanced cardiac life support class, part of Pacific Partnership 2014, at Da Nang General Hospital in Da Nang, Vietnam, on June 10.

Pacific Partnership, now in its ninth iteration, is the largest annual multilateral humanitarian assistance and disaster relief preparedness mission conducted in the Asia-Pacific region.

The 2014 mission, which began in late May, includes an enhanced role for Japan and simultaneous seaborne and airborne phases to improve disaster preparedness in five Southeast Asian host nations (Cambodia, Indonesia, the Philippines, Timor-Leste and Vietnam).

Pacific Partnership developed from the military-led humanitarian response to the 2004 tsunami that devastated parts of Southeast Asia. Building on the success of that operation, the U.S. hospital ship USNS Mercy returned to the region in 2006 for the inaugural Pacific Partnership mission. In successive missions, participants expanded to include partner-nation militaries and civilian nongovernmental organizations to increase the disaster-relief capabilities of host nations.