As there are no internal borders between Schengen countries in Europe, SIS compensates for border controls and is the most successful cooperation tool for border, immigration, police, customs and judicial authorities in the EU and the Schengen associated countries.

SIS is operational in most EU countries and the Schengen associated countries (Switzerland, Norway, Liechtenstein and Iceland).

In March 2023, SIS was renewed with new alerts, upgraded data and enhanced functionalities. 

Please, find more relevant information in link below.

https://old.uoou.cz/en/assets/File.ashx?id_org=200156&id_dokumenty=2255