The application of newly developed methods to localization of adrenal tumours has improved diagnostic accuracy, yet the challenge still exists. The sensitivity of ultrasound is too low for imaging small adrenal tumours, thus reducing sonography to a screening method. Computed tomography is a fast and sensitive localizing method, even for small tumours, with a low radiation exposure. Endocrine-active tumours with high hormone-secreting activity or displaying a tendency to additional extra-adrenal presentation will generally be best localized by scintigraphic imaging. Sonography and computed tomography as non-invasive methods and invasive puncture of the tumour or of the cyst with consequent cytological examination of the obtained material are most important procedures in the diagnosis of endocrine-inactive adrenal masses.