Level 1 - Global BPM (overview of EU Customs Business Domain and Global Business Data).

Level 2 - High Level BPM (interactions between the main business processes with each EU Customs Business Domain).

Level 3 - Business Requirement BPM (flow of the legal and business tasks within each main business process and the interactions between involved stakeholders).

Level 4 - Functional Requirement BPM (flow of the envisaged system; information exchanges; data rules and conditions; requirements trees; test cases and scenarios).