Interpretation of epidurograms may be difficult for those lacking experience, and most radiologists consider the epidural space to be outside their domain. This atlas will enable individual operators to explain the failure of a block, whether it is due to a misplaced or malfunctioning catheter, or an anatomical abnormality such as a septum or bony deformity. Complications such as subarachnoid, subdural or high epidural block produce characteristic appearances which are described. The results usually correlate well with the clinical history and may serve both the physician and patient in establishing sources of pain and stress, thereby avoiding any consequent medicolegal action.