The development of our knowledge of echinococcus disease has been outlined, and its etiology and distribution have been described. The disease is rare in this country, but not uncommon in other areas, and its increase may be expected because of conditions growing out of the War. Its diagnosis, especially in bone, is not difficult, if its possibility is realized, and if proper laboratory tests and roentgenograms are made. Treatment has been unsatisfactory to date. Marsupialization or sterilization of the cyst sometimes may be successful. Roentgen radiation has failed. Removal of the entire diseased area has removed the disease, but is mutilating. Insertion of bone chips will not be successful, unless the disease has been eradicated.