Fibroadenoma of the breast is a common cause of a benign breast lump in premenopausal women. The consensus view is that women with fibroadenomas are not at significant increased risk of developing breast cancer. Diagnosis is based on the combination of clinical examination, imaging and non-surgical tissue biopsy (the triple test). A clinical diagnosis of fibroadenoma alone is unreliable and does not exclude malignancy even in younger women. The choice of imaging is mammography, combined with ultrasound in older women, and ultrasound alone in younger women. Tissue biopsy, by either fine-needle aspiration or core biopsy, is the most accurate means of establishing the diagnosis. Traditionally, symptomatic fibroadenomas were treated by surgical excision, and this option should always be offered. There is increasing evidence that a conservative approach is safe and acceptable, provided the result of an adequate triple test is both negative for cancer and consistent with a fibroadenoma. Patients who choose conservative management need to be informed of the limitation of the tests, and must be assessed promptly if there is symptomatic or clinical change.