Named after the town in where the agreement was signed, the allows for the dissolution of internal borders and implementation of passport-free movement within its member nations. After taking effect in 1995, the Schengen Area is currently comprised of 26 European nations of which 22 are also members of the European Union. The four non-EU members are Iceland, Norway, Switzerland, and Liechtenstein, while the only six EU members outside the Schengen zone are Bulgaria, Croatia, Cyprus, Ireland, Romania, and the United Kingdom. Since its implementation, the Schengen agreement has eased the flow of both goods and services across the area providing a major economic benefit to member economies with people making , along with the crossing of . Naturally, this opening of borders has been instrumental in the growth of many industries across the Schengen zone, specifically tourism and transportation. However, after the recent terrorist attacks in France and Belgium, the Schengen Agreement, and all its associated economic benefits, could be in jeopardy.