The spine surgery lecture covers aetiology, pathogenic mechanisms and treatment of infections in spinal instrumentation, including low grade infections. Bacteria causing most operative spine infections are staphylococci or propionibacteria, and are derived from the patient’s skin. Skin prep does not eradicate these. Peri-operative measures including local high-dose antibiotic are necessary to reduce infection risk. Spine infections involve biofilms which are insusceptible to all except very high concentrations of antibiotics. Local measures for management of infection, including local antibiotic applications, and thorough debridement mean that, in most cases, metal can be retained.