Recent tendencies toward the reduction of diplomatic privileges and immunities have been justified by the decreasing importance of the causes which have contributed to their establishment in their present exaggerated extent. The traditional distrust of diplomatic missions as instruments of espionage and intrigue has all but vanished, and has been supplanted by an appreciation of their functions as agencies for facilitating the pacific intercourse of states. The scrupulousness with which the diplomatic character is now respected and the growing security of the legal order in most states make possible a reduction of diplomatic prerogatives without jeopardizing the successful and independent fulfillment of the mission which it is their purpose to secure. The widest pretensions to exemption from the authority of the receiving state were advanced at precisely those times in which diplomats were in practice subjected to the greatest amount of interference and control. Doctrines of the seventeenth and eighteenth centuries, inspired by a reaction against contemporary conditions, have been incorporated into the customary law, which has lost its raison d'Ure to the extent that the historical factors which influenced its growth are no longer operative. The need of the envoy for independence exists today no less than formerly, but it no longer requires, as a condition of its guarantee, that complete immunity from the law and jurisdiction of the receiving state which has found a figurative expression in the fiction of exterritoriality. As a subject involving few of the political factors which have thus far proved to be insurmountable obstacles in the way of codification, the law of diplomatic privileges and immunities is eminently suited for restatement and amendment in the form of a general convention. Such a restatement, if it is not to be retrogressive, must be based upon the conception that the receiving state has rights, and the sending state duties, which are correlative to the obligations of the state of residence and the rights of the appointing state, alone emphasized in the existing law.