Current advancements in imaging technology, especially three-dimensional/four-dimensional ultrasound and contrast-enhanced imaging, have increased the diagnostic yield of adnexal masses. The benefit of ultrasound is the characterization of an adnexal mass, suggesting the probable etiology of the mass. Masses may be divided as solid, cystic, or complex. It is predominantly the solid and complex masses that need a thorough evaluation. The role of color-flow imaging is now gaining importance and criteria for distinguishing between benign and malignant masses are often possible. Availability of a scoring system enables the differentiation of small adnexal masses. Several benign lesions may present as complex masses but can be distinguished and diagnosed on sonography. The availability of 3D ultrasound has been of great use to understand spatial relations and vascular morphology. Sonography allows a more detailed assessment of morphologic features of an adnexal mass. With a benign-appearing adnexal mass on sonography, the need for any further diagnostic tests is often obviated.