Incidental adrenal lesions are not uncommonly encountered in clinical practice. The adrenal glands are covered in routine scanning in both abdominal and chest computed tomography (CT) and magnetic resonance imaging (MRI). While a variety of diseases may affect the adrenal gland, the vast majority of incidentally discovered adrenal lesions in patients without a history of malignancy are benign. Consequently, the diagnostic approach to adrenal lesions in these individuals may not be as aggressive as that employed for oncologic patients. In this chapter, we explore clinically utilized adrenal imaging studies, as well as various adrenal diseases.