We analysed 68 cases of acetabular augmentation using the Wroblewski wedge for recurrent posterior dislocation of Charnley total hip replacements inserted through a posterior approach. The follow-up was done by postal questionnaire in living patients or by thorough search of case notes in the dead. All hips were followed up either until death or a minimum of 2 years. The average follow-up for the surviving successful group was 35.3 months. Out of 68 hips, 52 (76%) had no further dislocation at a mean follow-up of 35.3 months (range, 24-95 months). An additional 4 hips became stable after one closed reduction for a re-dislocation. After a second augmentation, 5 more hips were stabilised. Wroblewski wedge augmentation is a simple and effective procedure and should be considered before embarking on major revisions in recurrent posterior dislocations in the elderly with no obvious cause for instability.