human being, where the tissue and organ distribution, biological halflives, and excretion rates can be studied. Such investigations will be done by the use of whole-body gamma spectroscopy of the people and of sample materiais, and by radio chemical analysis of soli, food, and human excreta. Acknowledgenents The success of a mission of this type depends on the assistance of many individuals and organizations. The authors wish to express their sincere appreciation to those who participated and cthers too numerous to mention whose efforts contributed to the successful completion of the survey. We are particularly grateful to Dr. C. L, Dunham and his staff of the Division of Biology and Medicine of the Atomic Energy Commission and Dr. L. & Farr and many others at the Srockhaven National Laboratery for their enthusiastic support. The support of the Department of the Navy in furnishing an LST and transportation of the team as well as the assistance of the staff of the Naval Medical Research Institute, the Naval Radiological Defense Laboratory, the Commander in Chief of the Pacific Fleet, Naval Station Kwajalein, and the officers and men of the LST, Plumas County, was vital to the success of the mission. In the Marshall Islands we greatly appreciate the splendid assis- tance of the Trust Territory officials particularly Mr. Maynard Neas, Drs. .John Iaman, Trigar Ishoda, Nelson and many other Marshallese who assisted us. ~18-