The first efforts to formulate the norms banning the use of force were reflected in the 1928 Kellogg–Briand pact. In the contemporary international law, prohibition of force has gained an extremely immense significance with the balance of powers changing and the processes of globalisation picking up pace. Emerging threats and the legal character of how different states respond to them is one of the most pressing topics of today’s international law. Obviously, the authors of the Charter could not have foreseen the modern challenges for the international peace and security, like the threat of weapons of mass destruction and the terrorism. The peacekeeping forces, the peace agenda, the humanitarian intervention have come to be the new examples of response to the contemporary challenges for the international peace and security and of a flexible practical application of the Charter’s provisions.