Bedside duplex/color Doppler sonography is used for a wide gamut of abnormalities encountered in the neonatal intensive care unit. This article emphasizes the use of bedside sonography for evaluation of infants with necrotizing enterocolitis, infants requiring line placement, and those in whom a diaphragmatic abnormality is suspected. Although the assessment of those infants requires excellent operator skills, learning to do so is a definite benefit to these babies who would otherwise be exposed to ionizing radiation.