The Program on Forced Migration and Health is committed to professionalizing the field of humanitarian response. Natural and manmade catastrophes are among the greatest challenges to ensuring the health of populations. Tsunamis, hurricanes, and tornadoes have displaced millions in recent years. Armed conflicts continue to destroy communities, wreaking havoc on food, sanitation, and supply chains, and propelling survivors into fragile refugee camps. Increasingly, displaced persons are being forced into already overcrowded urban areas.