Improvements in abdominal imaging techniques have increased the detection of clinically inapparent adrenal masses, or incidentalomas (AI), the appropriate diagnosis and management of which have become a common clinical problem for health care professionals. Once an adrenal mass has been detected, the clinician needs to address two questions: 1) is the tumor hormonally active? and 2) is there any chance of the mass being malignant? The majority of AI is non-hypersecretory cortical adenomas, but an endocrine evaluation can lead to the identification of subtle hormone excess. An overnight low-dose dexamethasone suppression test, fractionated urinary or plasma metanephrine assay and, in hypertensive patients, establishing the upright plasma aldosterone/plasma renin activity ratio are recommended as preliminary screening steps. Masses greater than 4 cm are at greater risk of malignancy. Morphological imaging features may be helpful in the distinction between benign and malignant forms. Fine-needle aspiration biopsy is an important tool in the evaluation of oncological patients to establish any metastatic disease. Adrenalectomy is indicated by evidence of a functional adrenal mass, or a suspected malignant form. We advocate adrenalectomy of subtle hypercortisolism, especially in the presence of hypertension, obesity, diabetes or osteoporosis potentially aggravated by glucocorticoid excess. A close follow-up is needed, particularly in the first year after diagnosis.