Customs and Tax Administrations are the authorities carrying out state customs and tax policy, goods monitoring and payment of duties and charges and perform control on the movements of goods, execution of the procedures and payments of duties and charges. As the overall control is preformed in real time up-to-date customs systems operate within the processes linked to the companies systems through the messages interchange, namely completely automated.  

Cooperation in the development of customs information systems has been one of the main activities from the very beginning, from the foundation of the enterprise ZZI. Successful cooperation is noted between the Financial Administration of the Republic of Slovenia, Customs Administration and Customs Administration of Montenegro since both states gained their independence. When Slovenia joined the European Union the enterprise ZZI successfully developed new and customised customs solutions that Slovenia needed for the accession to the EU.

The customs systems are customised to the new requirements and directives of the advanced European customs operations and the EU requests and relying on the electronic data exchange, providing the customs simplified linking to the partners, customization of changes and the process of integration into the European customs system. 

The enterprise ZZI offers development, maintenance and upgrading of the modular but centralised customs and excise information systems.