Eighteen cases of iatrogenic femoral nerve injury are described. In two patients the damage was incurred as a result of an intra-abdominal operation. In three others the nerve was injured at the level of the inguinal ligament. In the majority femoral nerve palsy followed surgery to the hip joint and was attributable to a lesion-in-continuity. Only one of the patients in the series made a full recovery, but because only severe cases were included these disappointing results by no means represent the expected outcome. To avoid this serious and distressing complication of surgery, the surgeon must be familiar with the anatomic features of the region and must take care to avoid compression of the femoral nerve by retractors and its overstretching during operations on the the hip joint.