Benign fibro-osseous lesions of the jaws comprise a diverse group of conditions characterised by replacement of normal bone by fibroblasts, collagen fibers, and mineralized tissue. Some fibro-osseous jaw lesions clearly appear to be developmental disturbances, some represent dysplastic or reactive phenomena and others are regarded as benign neoplasms. Proper categorization of these lesions require correlation of the patient history and the clinical, radiographic, and operative findings with the microscopic features. Diagnosis based on histologic appearance alone is often impossible due to the overlapping histological features found in the various types of lesions.