Terrible triad of the elbow associates posterior dislocation, radial head fracture and coronoid process fracture. It is a complex trauma, associating severe bone and ligament lesions, with high more-or-less long-term risk of residual instability, stiffness, pain and osteoarthritis. During the last 20 years, pathologic, biomechanical and clinical knowledge has greatly progressed. Prevention of these severe complications requires initial understanding of the lesion mechanism and precise analysis of all lesions. Surgery aims to restore perfect stability by sequential anatomic repair, enabling early mobilization to prevent onset of stiffness. The aims of the present paper were to summarize the anatomic and pathophysiological bases, highlight the crucial importance of the humeroradial column and lateral collateral ligament, and to determine the importance of the coronoid process. Some aspects of treatment are controversial: systematic medial collateral ligament repair, or use of an articulated external fixator. Finally, we propose a simple algorithm to guide repair.