 Reducing infections caused by S. aureus is essential. The knowledge that colonization at a few key body sites such as the nose and the gastrointestinal tract is a prerequisite for infection2 ,3 offers an opportunity for therapeutic intervention. Thirty percent of the population has nasal colonization with S. aureus. In the last few years, decolonization agents such as mupirocin topical ointment and oral antibiotics such as doxycycline and rifampin have been studied for their utility in reducing colonization. However, these options have limitations in that recolonization is common, the impact of these interventions on multiple sites of colonization has not been assessed and resistance develops frequently to any of these, especially the oral antibiotics. Resistance in S. aureus has been designated a public health crisis. Methicillin-resistant S. aureus MRSA now accounts for 60 of all S. aureus infections. As an example of the growing crisis in S. aureus resistance, it should be noted that the number of MRSA infections rose from 2000 in 1993 to 368,000 in 2005. MRSA infections pose an even greater health and economic burden on the population than those caused by methicillin-sensitive S. aureus.4-8 S. aureus and MRSA infection trends in the VA health system mirror national trends5 and are associated with considerable morbidity and mortality in Veterans. A treatment that reduces S. aureus and MRSA colonization, without a risk of promoting antibiotic resistance could represent a breakthrough in decolonization therapy. Probiotics may be one such treatment option. 