All Western Balkan countries are, more or less, affected by the problem of modern day Islamic extremism and terrorism, which is, directly or indirectly, associated with the activity of the Islamic State in Iraq and Syria. The development of this terrorist organization is characterized by specific social conditions, created after the liquidation of Bin Laden, which practically minimized the role of Al-Qaeda as a global representative of Islamic terrorism. State-forming pretensions of the Islamic state, as a militant organization, indicate political goals, among which the most ambitious of all goals stands out - the creation of a Sunni- Muslim state with a Caliphate as the official form of government. The number of combatants, paramilitary and para-state structures indicate an unparalleled level of sophistication and the highest degree of organization that has ever been seen in a terrorist organization. Repatriated combatants from the Islamic State, who originate from the Western Balkans, represent an undisputable security challenge and a generator of violent extremist views, embodied in the examples of last year’s attacks on a police station in Zvornik, and clashes in Kumanovo. The current problem of uncontrolled influx of migrants who arrive from regions which are either under control of the Islamic State, or influenced by it, can reflect significant security consequences on the countries of the European Union, in which these migrants are settling in, but also on the transit countries of the Western Balkans.