Duplex/color Doppler ultrasound is the imaging modality of choice for the evaluation of soft tissue masses of the pediatric neck. Information regarding the size, shape, borders, location, internal consistency and vascularity of the mass, and its relationship to the major neck vessels may be rapidly obtained. If the lesion is too large to be completely imaged within the ultrasound field of view available or malignancy is suspected, computed radiography or magnetic resonance imaging is required before surgical removal. Scintigraphy is reserved for evaluation of midline masses, which are thought to be due to ectopic thyroid, to determine preoperatively if the mass is the patient's only functioning thyroid tissue. Correlation of the sonographic findings with the clinical information narrows the differential diagnosis; thus, more appropriate therapeutic decisions can be made. When indicated, ultrasound-guided interventional procedures can be performed for diagnosis and/or treatment.