fetal anomalies present postnatally corresponded very closely to those diagnosed prenatally. At 6 hours of life one of the conjoined twins had worsening congestive heart failure and at day 3 of life a successful urgent separation occurred for the pump twin while the anomalous acardiac twin expired. The pump twin continues to do well today but will need further surgical revisions. This is the first case of conjoined twins in which one twin had acardia and the pregnancy was managed with the assistance of Doppler and MRI in addition to ultrasound. To provide optimal treatment for infants with complex anomalies more than one imaging modality may be required and a multidisciplinary team approach is critical. Accurate prenatal diagnosis was critical in our case as urgent intervention was required.