The TIR Carnet is an international Customs document and constitutes the administrative backbone of the TIR system. It also provides proof of the existence of an international guarantee for the goods transported under the TIR system.

Under the supervision of the TIR Executive Board (TIRExB), the IRU is, at present, the only international organization authorized to centrally print and distribute TIR Carnets to its national guaranteeing associations under conditions set out in the Convention. Each national association in turn issues the TIR Carnets to transport operators in its country in accordance with the conditions set out in the declaration of commitment concluded between each transport operator and the association.

TIR Carnets are issued only to the TIR admitted transport operators by the national competent authorities.