This article will provide some background information regarding the systems put in place for the prevention, detection and correction of irregularities as a part of the management and control system of ESI Funds from the perspective of audit authorities. The process and principles for setting up and maintaining the system for irregularities is no different from any other parts of the management and control system. Also, the audit authorities’ work on this specific part follows the same principles that can be applied to auditing other parts of the system. Account must, however, be taken of the specificities of the national institutional framework and the audit approach taken must be adjusted according to national needs, rules and regulations.