This chapter explores corporate ethics as the set of responsibilities that firms bear toward the public good, understood through the framework of legal-political justice offered by New Natural Law. Business and society are not separate spheres but intrinsically interconnected: firms depend on social order, taxation, and regulation, while their activities directly shape public life. Corporate ethics is therefore framed as civic responsibility, where firms contribute to the common good of the polis by sustaining legality, paying taxes, and respecting institutions. The chapter examines the role of the state as the guarantor of social peace, clarifying the moral obligations of companies regarding taxation, duties, and the rejection of avoidance, evasion, and bribery. Beyond compliance, firms are called to cultivate civic virtue by supporting intermediate associations—such as cities, schools, and cultural institutions—and by fostering corporate citizenship through urban development, philanthropy, and values that transcend profit maximization. Finally, the chapter highlights the social dimension of work and the importance of unions as mediators of justice, as well as environmental stewardship and sustainability as extensions of the firm’s responsibility to future generations. Corporate ethics thus integrates economic success with civic participation, justice, and care for the common good.