Sonography is the first line modality for assessment of thyroid and parathyroid pathologies. Sonographic and color Doppler patterns of diffuse and focal pathologies of the thyroid are presented in this article. The accuracy of sonography in the localization of enlarged parathyroid glands is also discussed. The limitations of sonography in specifying focal thyroid diseases and the problems in localizing ectopic parathyroid adenoma are addressed.