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 4cm 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.