Analysis of fat samples from 130 subjects indicated that the general population of the US had a mean storage level of 4.0 parts per million (ppm) DDT and 7.8 ppm 1,1-dichloro-2,2-bis (p-chlorophenyl) ethylene (DDE). Geographic differences between samples taken in Phoenix, Atlanta, Louisville, and Wenatchee, Wash, were not evident. No difference between levels of DDT or DDE in the general population and in persons living in areas of extensive agricultural use of DDT were noted; however, occupationally-exposed workers had higher levels. Comparison of results of the present study with those of earlier surveys revealed no distinct directional trend in the storage level of DDT or DDE over the years between 1950 and 1962. The DDT storage level for the US was higher than for Canada, England, France, and West Germany, but about the same as for Hungary.