Research in international relations has identified a variety of actors who appear to influence U.S. foreign policy, including experts and “epistemic communities,” organized interests (especially business and labor), and ordinary citizens or “public opinion.” This research, however, has often focused on a single factor at a time, rather than systematically testing the relative importance of alternative possible influences. Using extensive survey data gathered over three decades we conduct a comparative test, attempting to account for the expressed foreign policy preferences of policy makers by means of the preferences of the general public and those of several distinct sets of elites. The results of cross-sectional and time-lagged analyses suggest that U.S. foreign policy is most heavily and consistently influenced by internationally oriented business leaders, followed by experts (who, however, may themselves be influenced by business). Labor appears to have significant but smaller impacts. The general public seems to have considerably less effect, except under particular conditions. These results generally hold over several different analytical models (including two-observation time series) and different clusters of issues (economic, military, and diplomatic), with some variations across different institutional settings (the U.S. House, Senate, and executive branch).