On 12 January 2010, a 7.0-magnitude earthquake devastated the island nation of Haiti, leading to the world's largest humanitarian effort in over 6 decades. The catastrophe caused massive destruction of homes and buildings and overwhelmed the Haitian health care system. The United States responded immediately with a massive relief effort, sending U.S. military forces and civilian volunteers to Haiti's aid and providing a tertiary care medical center aboard the USNS COMFORT hospital ship. The COMFORT offered sophisticated medical care to a geographically isolated population and helped to transfer resource-intensive patients from other treatment facilities. Working collaboratively with the surgical staff, ancillary services, and nursing staff, internists aboard the COMFORT were integral to supporting the mission of the hospital ship and provided high-level care to the casualties. This article provides the perspective of the U.S. Navy internists who participated in the initial response to the Haitian earthquake disaster onboard the COMFORT.