AllChlamydiaspecies are obligate intracellular bacterial parasites, and all are pathogenic to their various hosts [1].Chlamydia trachomatisandChlamydia pneumoniaeare human pathogens; the former being the etiologic agent for trachoma as well as a prevalent sexually transmitted bacterium, whileC. pneumoniaeis a respiratory pathogen responsible for community-acquired pneumonia. Both species disseminate from their sites of primary infection, and when they do so these organisms often take up long-term residence at distant anatomic locations. At sites of their dissemination, neitherC. trachomatisnorC. pneumoniaeproduces any known toxins. Rather, both species may elicit a powerful immunopathogenic response that in turn can engender various diseases, one of which is inflammatory arthritis [2]. In some individuals with acuteChlamydia-associated arthritis, the disease can become chronic. This article focuses on chronic arthritides attributable, or potentially attributable, to disseminated, persistent infection by theChlamydiae, and is intended primarily to stimulate discussion among researchers and clinicians regarding the unusual biology of these pathogens in relation to chronic disease. It is also intended to elicit discussion as to how knowledge of the biological attributes of chlamydial persistence might influence development of new therapies for treatment of that disease.