A case report is presented of the prenatal diagnosis of conjoined twins at 10 weeks and 2 days' gestation using three-dimensional ultrasound (3D US). The multiplanar display coupled with 3D US surface rendering clearly confirmed the presence of craniopagus. The twins were facing in opposite directions with the left occipital region of one embryo fused with the left parietal-temporal region of the other. Additional multiplanar analysis above the level of the biparietal diameter demonstrated brain sharing.