The ASM Sentinel Laboratory Guideline for Yersinia pestis, was revised by its author, Susan E. Sharp, to include updated information on the number of cases and when most cases occur in the United States.  The guideline is designed to assist Sentinel Level Clinical Microbiology Laboratories with information and techniques to rule out and refer specimens to Laboratory Response Network (LRN) reference laboratories for confirmation. ASM Sentinel protocols/guidelines offer clinical microbiology laboratories standardized, practical methods to aid microbiologists in ruling out critical agents that may be used in a bioterrorist event or associated with an emerging infectious disease. To download this and other sentinel level guidelines, go to http://www.asm.org/Sentinelguidelines.