Two cases of bilateral extradural haematomas are reported. In case I, the haematomas developed simultaneously and were probably due to a tear in the sagittal sinus. In case II, the haematomas developed sequentially and were demonstrated by serial CT scannings after the removal of a seemingly unilateral lesion. A review of the literature points out the rarity of this condition which had been described even before the CT era, with varying clinical presentations and unusually poor surgical results. The advent of the CT has made the diagnosis of simultaneous bilateral extradural haematomas easier and is regarded as a significant factor in the improvement of the prognosis noted in recent reports. However, the possibility of delayed bilateral extradural haematomas escaping detection in the initial CT should be emphasized. This unusual clinical presentation stresses the value of a routine use of serial CT scannings in the acute phase of head injuries.