The nature and duration of pain associated with herpes tester is highl
y variable. This review of research on pain in acute herpes tester and
postherpetic neuralgia (PHN) explores those observations relevant to
the definition and pathogenesis of PHN and the design of treatment tri
als. A model for the pathogenesis of PHN is presented, which gains sup
port from studies of risk factors. Several directions for future resea
rch are identified.