Routine use of pertussis vaccines has diminished the incidence of this disease but has not eliminated the pathogen. Pertussis remains a significant cause of disease in both very young infants and in the adolescent and adult populations. Acellular pertussis vaccines have fewer adverse reactions compared with whole-cell pertussis vaccines. Although efficacious against severe disease, current vaccines may not be as efficacious against milder forms of infection. New methodologies for understanding disease pathogenesis, immune responses and vaccine development are needed to effectively interrupt continued transmission of this pathogen.