The objective of the study is to analyse the professional requirements related to the treatment of assertions regarding the key aspects of the audit in the context of reporting missions. The audit of the financial statements must monitor whether the data collection and processing procedures are well established and permanently applied. The idea that it is the duty of the auditor to detect violations of the legislation is unanimously shared. At the same time, the auditor cannot be expected to report issues that do not belong to his competence. Mistakes in financial statements can be committed not only because of non-compliance with the principles of accounting standards, but also for other reasons explained in the article. In order to discover the errors and frauds listed above, the procedures recommended by the International Auditing Standards and those proposed in this paper can be extended. Statements or assertions made by management through the financial statements are grouped in various ways, which are not limited to the accurate presentation of financial information. By stating that the financial statements are in accordance with the applicable general financial reporting framework, it can be concluded that management implicitly or explicitly makes assertions about the recognition, measurement, description and presentation of various elements of the financial statements and related presentations.In practice, all cases of incorrect financial reporting is a serious problem for accountants who want to properly apply accounting provisions, but it is also a challenge for independent auditors. The objective of the audit is to ensure that the turnover of the accounts is correctly presented in the financial statements in accordance with the applicable financial reporting framework. It is important that when starting the audit, the auditor will first of all obtain a sufficient understanding of the terms and conditions of the engagement.