Regular summits provide basis for negotiations, but their success is based on the frequency and duration. Frequently organized and long meetings enable the participants to reach some conclusions and solve problems. Moreover, due to the length of such meetings, there is room for re-negotiation unless parties don’t reach a conclusion in the first trial. In time, as these summits are regularly convened, their principles are specified and their efficiency increases. More importantly, regular meetings allow leaders to prepare before sessions and learn details of issues discussed in these meetings as well as characteristics and tendencies of their counterparts. Summits are effective tools to conclude negotiations discussed in international forums successfully. In order to reach conclusions satisfactory for both sides, leaders push hard for succeed in these summits, so the “diplomatic momentum” between two summits continues. Regular meetings of European Union (EU) leaders are important examples of these meetings.