17 disciplines. The implementation of such a concept deserves careful consideration of the area to be studied. Rongelap Atoll has a unigue advantage since it has been contaminated only once by moderately high levels of fallout. Thus the time of origin is known without the confusion due to repeated contamination of the same area. There is what might be thought of as a disadvantage, the fact that atolls are not typical of continental situations. On the other hand, a glance at a map of the Pacific Ocean quickly shows that a large portion of the earth's surface is represented by atolls and other coralline islands. Late in 1958 the University of Washington, Laboratory of Radiation Biology, under the direction of Professor Lauren R. Donaldson, was asked to institute a program of "radiation ecology" at Rongelap Atoll. The first expedition was made in March 1958 in cooperation with a medical team headed by Dr. Robert A. Conard of the Brookhaven National Laboratories. have been made in August-September, March, Since that time trips 1958 by the ecology group and 1959 by the medical: and ecology groups. It should be emphasized that radiation effects on the biota are too elusive to be profitably followed in the field. Dele- terious effects are produced by a variety of agents which are not all known and are difficult to separate under field conditions. It has never been possible to determine with certainty that observed “abnormalities” of the biota in the vicinity of the