A non-isotopic nucleic probe (Accuprobe) has been presented recently by Gen-Probe for the direct specific 1-h identification of Staphylococcus aureus isolated from culture. 50 S aureus strains previously characterized by conventional methods as well as 26 atypical strains (absence of coagulase, thermonuclease and fibrinogen affinity factor) were tested. Moreover, the Accuprobe system was evaluated using 29 other staphylococcal type strains representing all the species described to date. Only the strains that belonged to the S aureus species, including the 26 atypical strains, were detected by Accuprobe, which proved to be a rapid specific mean of identifying S aureus strains, particularly those that are not readily identified by conventional methods.