Corporate governance as a system of control mechanisms is the response of modern companies to the new challenges that modern times impose on their business. The basic mechanisms of corporate governance include internal audit, audit committee and external audit. Apart from the fact that their separate roles entail different tasks and structure of work, a great challenge in their work is ensuring their cooperation and interaction. Meaningful and frequent communication can achieve the predetermined goals and overcome existing risks. The role of internal audit is focused on optimizing resources, reducing risks and conducting internal controls. Audit committee provides support and assistance to the board of directors in overseeing the external auditor, financial statements, conducting internal audits and many other tasks associated with supervision, preparation and selection. External audit examines and evaluates the financial statements, data and methods used in their preparation, and provides an independent, expert opinion on the objectivity, reliability and truthfulness of the financial condition, cash flows and results of operations. All three mechanisms operate in compliance with legal norms and regulations. The analysis of a public interest entity has revealed the competitiveness of these corporate governance mechanisms, whereby increasing the frequency and quality of their cooperation could lead to further advancement of the company. The cooperation of corporate governance mechanisms leads to accuracy, credibility, objectivity of certain phenomena and processes, validity of financial statements, high quality of internal controls, elimination of risks, shortcomings, possible fraud and ultimately, increased company profits.