This article reviews the epidemiology, risk factors, pathogenesis, diagnosis, treatment, and prophylaxis of ventilator-associated pneumonia (VAP), which is one of the most important infectious complications during the perioperative period. The definition of VAP is a nosocomial pneumonia occurring more than 48 h after endotracheal intubation and initiation of mechanical ventilation. Early liberation from the ventilator and the use of non-invasive positive-pressure ventilation are useful in preventing VAP. The early institution of appropriate antimicrobial therapy contributes to a good outcome. The initial therapy to ensure adequate coverage of potentially infective organisms should be accompanied by deescalation, or discontinuation, when the microbiological data became available. Useful preventative strategies include subglottic suctioning of pooled secretions just above the endotracheal tube cuff and oral care because of the pathogenesis of VAP.