Pertussis is a potentially serious vaccine-preventable disease. Many clinicians are unaware that pertussis is common in adults, and that adults are a major reservoir of the disease in the United States. A MEDLINE search was conducted of all English-language articles pertinent to pertussis infections in adults. Results of relevant articles were compiled into a narrative review. Studies have shown that sporadic cases of pertussis in adults are common in a variety of clinical settings. Patients typicall+pressnt with a prolonged cough illness preceded by upper respiratory symptoms. Widespread outbreaks of pertussis occasionally occur in high schools, college campuses, and healthcare settings. The diagnosis and treatment of adults with pertussis are reviewed. Pertussis infection, because of waning immunity, is common i n adults. Routine bqoster immunization of adults with the newer acellular vaccine may lead to the elimination of the disease in both children and adults.