Diplomacy is not foreign policy. Foreign policy is the attitude struck by one state towards another; diplomacy is one of a number of instruments employed in order to make that attitude persuasive. It would, however, be wrong to describe diplomacy as an ‘instrument of conflict’ and thus place it in the same category as secret intelligence, force, economic statecraft and propaganda. Like these, it is certainly an instrument of foreign policy; however, only diplo macy emphasises the idea that states have common, as well as conflicting, interests. Diplomacy, in other words, is an institution o f the states-system in a way in which what I have called the ‘instruments of conflict’ are not.