Although the incidence of mediastinal wound infection in patients undergoing median sternotomy for cardiopulmonary bypass is less than 1%, its associated morbidity, mortality, and "cost" remain unacceptably high. There is considerable lack of consensus regarding the ideal operative treatment of complicated median sternotomy wounds. The aim of this article is to review the current preventive, diagnostic, and therapeutic techniques offered to patients with mediastinitis. We also propose a new classification for postoperative mediastinitis. Data from the English-language literature suggest that the type of mediastinitis and direct assessment of the mediastinum under general anesthesia are the main determinants of the nature of subsequent operative treatment. Wound debridement and removal of foreign materials are essential steps of whatever procedures are applied. Closed mediastinal irrigation can be successful in type I mediastinitis, whereas major reconstructive operation is probably the treatment of choice for patients with mediastinitis types II to V. Refinement of the current diagnostic tools and further evaluation of the benefits of primary sternal fixation in combination with a reconstructive procedure in mediastinitis types I to III could improve the outcome of this dreaded complication.