Introduction In 1976, Brookhaven National Laboratory initiated a program of external radiation survey for the Rongelap, Rongerik, Ailuk, Wotje and Utirik Atolls. The purpose of these surveys was cto provide sufficient information concerning the ambience radiation levels resulting from the mid 1950's weapons testing program to make external dose calculations for the individuals Living in the surveyed areas. During the last two years, sufficient measurements were made to provide external dose information for most of the populations in the region. The data from Rongerik, Ailuk, Wotje, Rongelap and Utirik Atolls were acquired during trips in September 1976, May 1977 and Ocrober 1977. All the exposure rate information gathered from these atolls was obtained with a pressurized ion chamber. The equipment used in these studies consisted of a Reuter Stokes Environmental Radiation Monitor, Model RSS-111 and a gamma spectroscopy system consisting of a sodium iodide detector coupled to a portable multichannel analyzer. Environ- mental exposure levels were assessed via the RSS-111, and the NaI gamma spectrometer was used to determine the energy dependence correction factors for the RSS-ill instrument. The field trips were staffed by BNL personnel and guest sc.entists from other institutions. Participants are listed later in the report. This report represents all of the external exposure data collected to date dy 3NL from these atolls. From these data, we have made external exposure estimates for the people living on Rongelap, Ailuk, Wotije and Utirik Atolls.