Injury (trauma) is the leading cause of death in the United States for people younger than 45 years of age. Each day, more than 170,000 men, women, and children are injured severely enough to seek medical care. About 400 of these people will die and another 200 will sustain a long-term disability as a result of their injuries. An estimated 20-40% of trauma-related deaths could be prevented if all Americans lived in communities that were served by a well-organized system of trauma care. This Issue Brief describes a new computer model that can help State and regional policymakers decide where to place designated trauma hospitals and helicopter depots to maximize their residents’ access to trauma care.