For many years various types of materials have been employed in the repair of skull defects. The most recent substance to be used is the element tantalum. The contributions of Olsen,1Pudenz,2Burke,3Fulcher,4Robertson,5Baker,6Robertson and Peacher,7Schnitker and McCarthy,8Woodhall and Spurling,9Turner,10Gardner,11Echols and Colclough12and Bradford and Livingston13have done much to popularize the use of this element for such procedures both in military and civilian practice. Early débridement, skilful medical care and the use of sulfonamide drugs and antibiotics have been instrumental in saving large numbers of patients with compound depressed skull fractures. Of primary importance in the treatment of these patients is the débridement of the soft tissues, including the brain, dura and scalp. At this time a decision must be made as to whether the skull defect should