Fetal and perinatal medicine is a rapidly expanding field, and noninvasive imaging by means of ultrasonography and MRI is playing a major role in refining diagnosis and therapy. Recent technological advances in these imaging modalities now allow unprecedented morphological depiction of the fetus and excellent insight into complex pathologic conditions, as well as yielding superior guidance for therapeutic fetal inter ventions. I am very pleased that Professor F. Avni, a leading international pediatric radiologist, was prepared to take on the challenging task of preparing and editing this...