The effect of repeated external cephalic version, performed at between 33 and 40 weeks gestation, on presentation at delivery was studied in a randomized controlled trial comprising 180 pregnant women with breech presentation. No tocolysis, analgesia or anaesthesia was used. Approximately 25% of all attempts in the study group of 90 women were successful; repeated external version resulted in cephalic presentation at delivery in 48% of patients. Spontaneous version to cephalic presentation occurred in 23 (26%) of the 90 women in the control group in whom version was not attempted, indicating a therapeutic gain from the procedure of 22%, with a 95% confidence interval of 8 to 35%. No severe complications of external cephalic version were noted. We conclude that external cephalic version reduces the frequency of breech presentation at delivery. This mainly benefits the mother because of the decrease in the number of caesarean sections and their inherent maternal morbidity.