External version was attempted in 70 pregnancies with foetuses in breech presentation near term. Version was successful in 50 patients (71%), 40 of whom delivered vaginally (80%). Of the 20 patients in whom version was not successful, only 7 patients (35%) delivered vaginally. 2 patients required immediate Caesarean section after attempted version because of ominous foetal heart rate patterns. We analysed the sonographic parameters associated with successful version. The location of the placenta, amount of amniotic fluid, foetal biometry (estimated foetal weight, cephalic circumference, abdominal diameter, femur length) and extension or flexion of the foetal head were analysed. Only extended legs correlated with the success of the procedure. The results suggest, that ultrasonography is an important prerequisite for successful version of a foetus in breech presentation near term.