The late results of early treatment of congenital dislocation of the hip in the von Rosen splint have been recorded in a follow-up study of 111 children with an average age of ten years (range eight to sixteen). The clinical diagnosis had been made within two days of birth and in most cases confirmed by radiological examination. Splintage was in all cases begun within the first few days and maintained for an average period of ten weeks. Two cases of failure of the initial treatment were encountered but had good final results. The follow-up study included a radiological examination in which were recorded the general configuration of the joint, the CE-angle described by Wiberg, the presence or absence of an os acetabuli and the roundness of the femoral head. The findings were compared with those in a control group of 222 normal children. All the treated hips developed normally except for a single case of minor dysplasia and a single case of slight enlargement of the femoral head and neck following appearances suggestive of avascular necrosis at the age of two years.