Agent Orange was an herbicide used during the Vietnam War to kill unwanted plants and to remove foliage which hid enemy combatants. The U.S. used more than 19 million gallons of herbicides for defoliation, 11 million gallons of which consisted of Agent Orange. Agent Orange has been shown to cause various health problems due to trace amounts of TCDD (dioxin). This fact sheet describes how concerned veterans can obtain examinations with their veteran's benefits, and that they may be eligible for disability compensation for Agent-Orange related illnesses.
The Department of Veterans Affairs: http://www.va.gov/