 Surgical-site infections SSIs occur in up to 500,000 patients per year in the United States. Patients with SSIs require significantly longer hospital stays and higher healthcare expenditures. In fact, it is estimated that SSIs are responsible for almost 4 million excess hospital days and billions of dollars in added hospital charges every year. Additionally, SSIs are a significant source of morbidity and mortality for surgical patients 5,8. Thus, prompt and definitive measures are necessary in order to redress this significant public health concern. Over the past few decades, the implementation of a number of preventative measuresincluding improved techniques in preoperative skin antisepsis and antibiotic prophylaxis have led to significant reductions in the rate of SSIs. Studies have demonstrated that approximately half of all SSIs are preventable with the proper use of prophylactic antibiotics. Despite these dramatic improvements, SSIs remain a tremendous burden on the healthcare system. Furthermore, routine use of systemic antibiotic prophylaxis is not without risks, as it may lead to rapid development of antibiotic resistance, and also exposes patients to undesirable systemic drug effects. The purpose of this study is to evaluate the ability of topical vancomycin to reduce surgical site infections after neurosurgical operations. 