Good faith (bona fides) is presented in the Civil Code of the Russian Federation as a general principle and presumption. In resolving corporate disputes, the courts are governed by general principles of good faith. However, corporate relations have a specificity due to, inter alia, the variety of corporate forms. It can be assumed that the application of good faith provisions should also vary taking into account the characteristics of corporate patterns, the types and forms of corporate relations, subjective internal corporate circumstances. Common law countries have developed a system of good faith elements and special tests to apply the required requirement of good faith according to the context. A special place is given to fiduciary relations as a product of bona fides. The author has carried out a comparative analysis of the provisions of the Plenums of the Supreme Court of the Russian Federation, the Supreme Court of the Russian Federation and the law enforcement practice of Germany, the USA, Great Britain and Canada on the issues of good faith in the consideration of corporate disputes. Special attention is paid to the interrelation between corporate ethics and law. Examining a number of key cases from the law-enforcement practice of the courts of the Anglo-American system of law, the author substantiates the possibility of applying special tests, namely, objective and subjective good faith tests, to regulate matters related to the application of the rules of good faith from the Civil Code and special laws in dealing with corporate disputes. Special attention is paid to the role of courts and permissible discretion in the formation of standards of enforcement of blanket norms and general principles of law in corporate relations.