Companies’ day-to-day operations often require them to address ethical dilemmas and make ethical decisions. The corporate scandals that we have witnessed in recent decades evidence the failure to deal effectively with these situations and with the associated financial losses, reputation damage, and generation of a climate of distrust. Despite the attempts of regulatory reforms proposed in the wake of these scandals, these reforms are shown to be insufficient, making it necessary to reinforce an ethical culture inside organizations. A good system of internal control and monitoring, combined with appropriate mechanisms of corporate governance, among other aspects, can form the basis on which to promote an ethical climate and prevent misconduct. Of the aspects related to corporate governance, special emphasis has been placed on the importance of ethical leadership, both for directors and for managers at different levels. This ethical leadership may contribute to reinforcing an ethical culture and promoting other formal tools, such as ethical codes or internal reporting channels for whistleblowers, which are effective in preventing and detecting unethical behavior. This chapter focuses on identifying the features related to the Board of Directors (such as its independence or its diversity) that can promote the implementation and effectiveness of whistleblowing channels or ethical codes and how they can contribute to reinforcing and extending an ethical culture throughout an organization.