The resistance topic is timely given current events. The emergence of mysterious new diseases, such as SARS, and the looming threat of bioterrorist attacks remind us of how vulnerable we can be to infectious agents.   With advances in medical technologies, we have tamed many former microbial foes, yet with few new antimicrobial agents and vaccines in the pipeline, and rapidly increasing drug resistance among infectious microbes, we teeter on the brink of losing the upperhand in our ongoing struggle against these foes, old and new.