Perineural blocks with catheter placement are more and more frequently used. Few data dealing with infectious complications of perineural catheters exist. We assess incidence and localization of infectious complications of perineural catheters by means of computerized data acquisition. We prospectively evaluate perineural catheters placed at different sites for regional anesthesia and postoperative analgesia. The catheters were placed under standardized sterile conditions by using the nerve stimulator technique. Local inflammation is defined as the presence of at least two of the three signs: redness, pain on pressure or swelling. Infection is defined as the presence of at least two of the following criteria: pus at the catheter insertion site, fever, increased CRP and/or leukocytes requiring antibiotic therapy.