Many servicemembers who served in the Persian Gulf War have subsequently experienced health problems such as fatigue, muscle and joint pain, gastrointestinal complaints, headaches, memory loss, and sleep disturbances. Whether these health problems are related to these servicemembers' exposures to chemical, biological, or environmental agents during their Gulf War service has been a topic of much controversy. To ensure that all issues related to Gulf War illnesses were comprehensively addressed, the Department of Defense (DOD) established the Office of the Special Assistant for Gulf War Illnesses (OsAGwI) in November 1996. To determine whether DOD is diligently addressing issues related to Gulf War illnesses, the Ranking Minority Member of the House Committee on Veterans Affairs asked GAO to examine selected OSAGWI operations. Specifically, GAO'S objectives were to (1) describe DOD's progress in establishing an organization to address Gulf War illnesses issues and (2) evaluate the thoroughness of OSAGWI'S investigations into and reporting on incidents of veterans' potential exposure to chemical or biological warfare agents during the Gulf War.