In this article, the functions of political appointees have been classified by an index on the relation between politics and bureaucracy. Based on that classification, the real states of four democracies, the United States, the United Kingdom, France and Japan, have been examined. From this study, the causation consisting of the politico-administrative relation (concretely, the insider-outsider factor and the line-staff factor), the independent value, and the political appointees' functions (advice, decision-making and interface between politicians and civil servants), the dependent value, has been confirmed. Through this examination from a comparative perspective, a proposal of generalization about the political appointees' functions has been presented.