Regulation (EU) No 537/2014, which refers to specific requirements in relation to the statutory audit of public interest entities, in addition to the established requirements in relation to the carrying out of the statutory audit of annual accounts and consolidated accounts of public interest entities, organisational rules as well as rules related to the selection of audit firms and approved statutory auditors have also been established in order to promote their independence, i.e. to avoid conflicts of interest and to reduce the impact on the quality of the audits carried out. In addition to strengthening the supervision and control of the reliability of financial reporting and reviewing the procedures for the application of the legal requirements and the regulation of the audit committee, the Regulation also prescribes the mandatory rotation of audit firms and statutory auditors as well as the limitation of non-audit services and the determination of the percentage value of the remuneration from the provision of non-audit services by the statutory auditor. Mandatory audit firm rotation limits the number of years an audit firm can audit a client's financial statements and has been proposed as a means of preserving auditor independence and enhancing public confidence. Threats to auditor quality and independence, as well as conflicts of interest, are often related to the duration of the audit engagement, i.e. the development of a long-term relationship between auditors and clients. This paper elaborates on the importance of mandatory rotation of audit firms and auditors, its impact on the quality and independence of the audit opinion, as well as the relationship of rotation with the duration of the audit engagement, which may lead to conflicts of interest and breaches of professional ethics.