Staphylococcus aureus is one of the most common causes of both hospital- and community-acquired infection worldwide. Since the emergence of methicillin-resistant S. aureus (MRSA) in the 1980s in the United States, vancomycin has been the antimicrobial agent of choice for serious MRSA infections. S. aureus with reduced susceptibility to vancomycin (minimum inhibitory concentration [MIC]=8 micro/mL) was first reported to have caused infection in a patient in Japan in May 1996. In August 1997, the first S. aureus isolate intermediately resistant to vancomycin (VISA; MIC=8 micro/mL) in the United States was reported in Michigan. This report updates the ongoing investigation in Michigan and describes preliminary findings of the ongoing investigation of a second case of VISA infection in a patient in New Jersey.