Agent Orange is one of several herbicides sprayed by the U.S. government in Vietnam in the 1960s and 1970s as a defoliant. It contains tetrachlorodibenzo-para-dioxin (dioxin), a chemical that the Environmental Protection Agency and the Occupational Safety and Health Administration have classified as highly toxic and carcinogenic. DOD sprayed an estimated 11 million gallons of Agent Orange in Vietnam during the war. In the ensuing years, dioxin has been a focus of research and has been associated with a number of latent illnesses, including cancer and most recently diabetes, which have developed among people who have been exposed to the chemical. The use of Agent Orange has also spawned much litigation over the years, including suits against the manufacturers of the product and against the United States. Until 1991, when Congress passed the Agent Orange Act, military veterans who believed their illnesses were caused by dioxin exposure had limited success in obtaining medical benefits and other compensation. Previously, the VA had denied benefits to most veterans who claimed adverse health effects from the herbicide because poor records made it difficult for many of them to demonstrate where and when they had come into contact with the chemical, and because VA had not accepted proof of a direct link between certain illnesses and dioxin. The Agent Orange Act subsequently authorized awards on the presumption that any veteran who served in Vietnam and who develops certain diseases identified by the National Academy of Sciences’ Institute of Medicine (IOM) and accepted by VA had been exposed to Agent Orange. The act also gave VA responsibility for providing information to veterans about health conditions related to Agent Orange exposure and assistance in preparing their claims. Over time, the body of research on the health effects of dioxin exposure has grown, and in recent years, research organizations such as IOM have learned more about positive associations between exposure and certain medical conditions. Further, both the National Institutes of Health and the Environmental Protection Agency consider dioxin a carcinogen on the basis of studies showing associations between exposure and medical conditions such as lung cancer. Under the Agent Orange Act, IOM is required to review and analyze all medical research on dioxin exposure every 2 years and advise VA on the degree to which it believes Agent Orange is associated with certain health conditions. On the basis of this research, VA has accepted a number of medical conditions associated with Agent Orange exposure. Most of these conditions are types of cancers, such as non-Hodgkin’s lymphoma and soft-tissue sarcomas, or skin disorders, such as chloracne. More recently, prostate cancer and diabetes were added to the list after research showed a higher than expected rate of these conditions among those exposed to dioxin. (See fig. 1.) Federal employees and employees who worked under contract to the U.S. government in Vietnam are not covered by the Agent Orange Act. Rather, federal employees who are injured or become ill as a result of their employment, including those who worked in Vietnam, may file a claim under FECA, a comprehensive workers’ compensation law for federal employees. To obtain benefits under FECA, claimants must show that (1) they were employed by the U.S. government, (2) they were injured (exposed) in the workplace, (3) they have filed a claim in a timely manner, (4) they have a disabling medical condition, and (5) there is a causal link between their medical condition and the injury or exposure. Unlike veterans, federal employees who file claims under FECA based on Agent Orange exposure must demonstrate that they were personally exposed to Agent Orange while in Vietnam and that their medical conditions were “proximately caused” by this exposure, (i.e., that there was a causal link between the exposure and their condition). Labor has primary responsibility for processing all FECA claims and has assigned the processing of special types of claims, such as those for Agent Orange exposure, to specific OWCP offices. Labor also processes all appeals from claimants regarding claims that were denied. Claimants have three levels of appeal: (1) reconsideration by an OWCP claims examiner, (2) a hearing or review of the written record by OWCP’s Branch of Hearings and Review, and (3) a review by the Employees’ Compensation Appeals Board. Either a request for reconsideration by a senior claims examiner not involved in the initial decision or a hearing request is generally the first level of appeal, followed by an appeal to the Employees’ Compensation Appeals Board. A decision of the Employees’ Compensation Appeals Board is final—claimants cannot appeal Labor’s decisions in federal court. However, if new evidence becomes available after the decision, the claimant can request the claim be reopened for reconsideration and further review by Employees’ Compensation Appeals Board. Workers’ compensation coverage for employees who work under contract to the U. S. government outside the United States is provided by the employing contractor under DBA. Under DBA, individuals who can show that they were harmed and that working conditions could have caused this harm are entitled to a presumption that their claims are work-related and valid. Claimants must also establish that their claim was filed timely and show proof of employment, exposure to Agent Orange, a disabling medical condition, and that their condition arose naturally out of employment (i.e., that their condition was related to their employment in Vietnam). Under DBA, Labor is required to license the insurance carriers that provide the employers’ workers’ compensation coverage. To prevent employers and insurance carriers from an undue financial burden for insuring employees during a time of armed conflict, Congress enacted the War Hazards Compensation Act, which allows insurance carriers to obtain reimbursement from Labor when a claim is paid for an injury or death caused by a “war-risk hazard.” Contract employees who are injured file workers’ compensation claims directly with their employers and their employers’ private insurance carriers. The insurance carrier may either accept or “controvert” (deny) the claim. Claimants may request that OWCP review the insurance carrier’s decision and may ask for a hearing with one of Labor’s administrative law judges. The administrative law judge issues a decision and order awarding or denying benefits. Claimants may appeal an administrative law judge’s decision to Labor’s Benefits Review Board. Claimants may also obtain review of the Benefits Review Board’s decisions in federal court. Many of the agencies we contacted were unable to locate records on federal and contract workers employed in Vietnam, but on the basis of the limited data available, we estimated that at least 72,000 civilian employees and as many as 171,000 may have worked in Vietnam between 1964 and 1974. We developed these estimates using data we obtained from the Department of State and DOD but were unable to determine the reliability of the data. Most of the federal agencies we identified as likely to have had employees in Vietnam—DOD, CIA, and the Departments of State, Agriculture, and Treasury—were unable to provide us with the exact number of civilian employees they had working in Vietnam during the war. Agency officials told us they had difficulty identifying these workers because personnel records were kept solely on paper, as computers were not in common use at that time. Agency officials told us that these paper records may have been destroyed or, if such records still exist, were not indexed or organized in searchable formats. In addition, the location of some records was unknown because of the loss of institutional knowledge resulting from staff turnover over the years. Both the State Department and DOD located some historical data that we used to develop estimates of the number of civilians who worked in Vietnam. Three of the five agencies we contacted—CIA and the Departments of Agriculture and Treasury—were unable to provide us with any data on the number of federal and contract employees they had working in Vietnam during the war. The Department of State was able to identify its federal employees who worked in Vietnam between January 1964 through November 1965 and January 1967 through November 1974 from published quarterly lists of employees, but the agency was unable to determine the number of employees working for the agency in Vietnam under contract. Although DOD officials were unable to locate data, we located historical reports of civilian personnel strength by year at DOD’s Directorate for Information, Operations, and Reports but were not able to obtain an unduplicated count of civilians who were in Vietnam between 1964 and 1974. This office later located service contract amounts during the Vietnam War period published in historical reports, from which we were able to estimate the number of contract employees. Using data from the Department of State and DOD, we estimated that at least 72,000 and as many as 171,000 civilian employees may have worked in Vietnam during the war. From the quarterly lists of employees provided to us by the Department of State, we estimated that the agency had about 6,000 employees in Vietnam between 1964 and 1974. To estimate the number of DOD federal employees, we used annual civilian personnel strength data from historical DOD reports and assumed a 2-year rotation similar to that of military personnel to develop an unduplicated count of about 4,600 employees. We obtained the personnel strength data from published DOD reports but were unable to determine how the data were collected; therefore, we were unable to determine the reliability of these data. To estimate the number of DOD contract employees, we obtained from DOD the dollar amount of DOD service contracts, by year from 1966 to 1974, where the workplace was Vietnam, and divided these annual amounts by a range of “burdened labor rate” estimates to calculate the number of employees represented by these contracts each year. However, DOD was unable to provide us with information on the range of salaries paid to contract employees in Vietnam. Therefore, for our analysis, we assumed annual salaries of $7,500, $15,000 and $25,000—-which represent a range of low, middle, and high salaries of federal employees during that time—to obtain burdened labor rates of $15,000, $30,000 and $50,000 per person.