Four varieties of swabs held in plastic containers and three swab transport media kits, all obtainable in the United Kingdom, were tested to assess their effectiveness in the isolation of Bordetella pertussis. The highest isolation rates up to 48 hours were obtained with Dacron swabs held in plastic containers. Swab-transport media kits proved unsatisfactory. B pertussis may have a stronger affinity to Dacron than to cotton-wool, and pernasal swabs should be made of Dacron to improve the recovery of B pertussis.