The availability of iron to potentially pathogenic bacterial strains is restricted by the iron-binding proteins of the host. In this study, we examined 40 strains of Campylobacter species grown under iron-limiting conditions. While the strains produced no detectable siderophores, all the isolates freely utilized exogenous siderophores produced by other organisms as iron carriers. These data suggest that the use of an exogenous siderophore (either purified or present in a coinfecting microorganism) may be important in developing a suitable laboratory model for campylobacteriosis.