Lastly, high-level meetings can be defined as meetings of leaders within the context of their official visits. Especially, newly elected leaders visit foreign countries and meet their counterparts. Such visits provide information about policies and characteristics and opinions of their counterparts. In addition, leaders aim at developing friendly relations and economic relations with the host country. To sum up, like bilateral and multilateral diplomacy, summit diplomacy is an important instrument of modern diplomacy. However, it needs to be underlined that these instruments are not mutually-exclusive. In other words, summit diplomacy can be used as a part of bilateral or multilateral diplomacy. Like bilateral and multilateral diplomacy, summit diplomacy has some advantages and disadvantages. The efficiency of these diplomatic instruments depend on the power and capabilities of states as well as the institutions using these instruments. Diplomatic missions, ministries of foreign affairs and non-state actors such as non-governmental organizations (NGOs) and multi-national companies (MNCs) are basic institutions of modern diplomacy.