This report presents tabular and graphical data on the characteristics of U.S. employed doctoral scientists and engineers, and includes data of the 1973 cohort; it augments data in a previous report, "Characteristics of Doctoral Scientists and Engineers in the United States, 1973," which reported on scientists and engineers who had received their doctorates through June 30, 1972. This publication evolved out of the National Science Foundation's Manpower Characteristics System, which was established to provide manpower data needed by many individuals and groups, particularly those engaged in science and engineering policy activities. A characteristic feature of the system is that information is collected from individual scientists and engineers rather than from other sources, e.g., employers and professional societies. The basis of this report is the first survey, in a biennial series, of the Doctoral Roster of Scientists and Engineers, conducted for the National Science Foundation by the Commission on Human Resources of the National Academy of Sciences. (Author/MLH)