McCune-Albright syndrome consists of polyostotic fibrous dysplasia, precocious puberty and cafè-au-lait skin lesions. Bone lesions are characterized by the presence of fibrous connective tissue with a characteristic whorled pattern and containing trabeculae of immature non-lamellar (woven) bone. They may be solitary (monostotic) or multiple (polyostotic). Commonly involved bones include the femur, tibia, ribs and facial skeleton. In the fibula pseudo-cystic areas and 'ground glass'-like areas, in the femur 'shepherd crook' deformation due to weight on a less resistant bone and secondary to many cortical microfractures, are typical. MRI gives the exact delimitation of the lesions and is especially indicated in the followup of monostotic forms and in the outcome of surgical corrections. Bone scintigraphy with technetium 99 is essential in the follow-up of the disease. Ultrasonography is very useful in ovarian cyst follow-up and in the detection of thyroid and adrenal nodules and testicular microlithiasis.