Introduction:Hurricane Katrina, a Category 3 hurricane, made landfall in August 2005. Approximately 1,500 deaths have been directly attributed to the hurricane, primarily in Louisiana and Mississippi. In New Orleans, Louisiana, most of the healthcare infrastructure was destroyed by flooding, and >200,000 residents became homeless. Many of these internally displaced persons received transitional housing in trailer parks (“villages”) under the auspices of the [US] Federal Emergency Management Agency (FEMA).Problem:The FEMA villages are isolated from residential communities, lack access to healthcare services, and have become unsafe environments. The trailers that house families have been found to be contaminated with formaldehyde.Methods:The Children's Health Fund, in partnership with the Mailman School of Public Health at Columbia University, began a program (“Operation Assist”) to provide health and mental health services within a medical home model. This program includes the Baton Rouge Children's Health Project (BRCHP), which consists of two mobile medical units (one medical and one mental health). Licensed professionals at the FEMA villages and other isolated communities provide care on these mobile units. Medical and psychiatric diagnoses from the BRCHP are summarized and case vignettes presented.Results:Immediately after the hurricane, prescription medications were difficult to obtain. Complaints of headache, nosebleeds, and stomachache were observed at an unusually frequent degree for young children, and were potentially attributable to formaldehyde exposure. Dermatological conditions included eczema, impetigo, methicillin-resistant staphylococcus aureus (MRSA) abscesses, and tinea corporis and capitis. These were especially difficult to treat because of unhygienic conditions in the trailers and ongoing formaldehyde exposure. Signs of pediatric under-nutrition included anemia, failure to thrive, and obesity. Utilization of initial mental health services was low due to pressing survival needs and concern about stigma. Once the mental health service became trusted in the community, frequent diagnoses for school-age children included disruptive behavior disorders and learning problems, with underlying depression, anxiety, and stress disorders. Mood and anxiety disorders and substance abuse were prevalent among the adolescents and adults, including parents.Conclusions:There is a critical and long-term need for medical and mental health services among affected populations following a disaster due to natural hazards. Most patients required both medical and mental health care, which underscores the value of co-locating these services.