The Department of Defense Global Emerging Infections Surveillance and Response System has a mission to identify vulnerabilities in the military health system related to the occurrence of emerging infectious diseases. Public health laboratory (PHL) functions are critical to the detection and control of emerging infectious diseases and were assessed. Four important services were evaluated: (1) surveillance for antibiotic resistance, (2) laboratory-based infectious disease surveillance, (3) provision of diagnostic services for uncommon infections, and (4) specimen referral and information transfer within a defined PHL infrastructure. Initial assessments identified several shortcomings and a lack of information about PHL functions. Therefore, a PHL symposium was held in September 1999 to define the state of civilian and military PHL functions, identify problems and interventions, and encourage civilian-military networking. After the symposium, selected attendees met in two workshop groups. One addressed the first two functions; the other addressed the last two.