Two cases of thoracic injuries with flail chest are described. Particularly, the indications and management of surgical treatment, of flail chest are discussed. It is important not to reconstitute the anatomic structure of the chest, but to recover the physiological respiratory motion. Today, the first choice is the mechanical ventilation, even if it needs a long period of time and sometimes it has some complications. The surgical treatment is absolute only when other thoracic lesion i.e. massive hemothorax, pulmonary, tracheal and bronchial injuries) joined the flail chest. Often the surgical management follows the ventilation therapy; in these cases, thoracotomy is better made in five or six days after trauma. Today, the Kirschner pins or Judet plates are used for fixation. Sometimes, when injury is considerable synthetic meshes are also used.