There is an increased interest in prevention of nosocomial infections and in the potential savings in healthcare costs. The aim of this review of recent studies on surgical site infections (SSIs) was to compare methods of cost research and magnitudes of costs due to SSI. The studies reviewed differ greatly with regard to study design and methods for cost calculation. However, healthcare costs for a patient with SSI are, on average, approximately twice the amount of costs for a patient without an SSI.