Since multiple pregnancies are of higher perinatal risk to diminish the rate of complications and stillbirth, the proper ultrasound management has to be done. Twins differ in zygosity, chorionicity, and amnionicity. Authors summarize how to diagnose the type of pregnancy and its complications in ultrasound examination and what to look for to achieve as much as possible of vital information. Authors propose some general rules for sonographers: • Prenatal US—the same schedule as in singletons for assessment of fetal morphology and markers of genetic abnormalities despite special schedule for twins. • Keep patient aware about the possibility of “vanishing twin.” • Set the chorionicity as early as possible. • Set the amnionicity in the first-trimester scan. • Look for the prognostic signs of twin-to-twin transfusion syndrome (TTTS) in the first- and second-trimester scan. • Monitor the amniotic fluid volume from 16th week gestational age (GA) on. • Monitor the fetal growth from the first-trimester scan on. • Doppler US and growth every 2 weeks in monochorionic (MC) twins or every week if suspicious signs occur from the 16th week of GA on; every 4–6 weeks in DC twins. • Exam the middle cerebral artery-peak systolic velocity (MCA-PSV) in MC from the mid-pregnancy on. • Look for the cervix incompetence and the risk of preterm delivery.