This report critically evaluates the impact of breaking up the Big Four audit firms on competition and the quality of audits of large companies. It examines arguments for and against the Big Four companies and their role in providing accounting services. The report highlights the advantages of the Big Four companies such as brand value, compliance with accounting standards, and self-selection outcome. It also discusses negative impacts such as involvement in scandals, failure to comply with regulations, and tax evasion. The report concludes that the role of the Big Four companies is crucial in maintaining the quality and standards of financial records of different enterprises.