This chapter explains the ethical foundations that support the delivery of financial products and services and increase market stability. In this chapter, market confidence is shown to rely on mutual trust that includes reciprocal trust and stakeholder reciprocity, where clients, firms, regulators, and society collectively uphold the duties of fairness and protection. The chapter situates ethics historically and philosophically (i.e., Aristotle and Aquinas to Kant, Mill, Smith, Rawls, and Kohlberg). The chapter then distinguishes between metaethics, normative ethics, and applied ethics, with a focus on normative ethics as the primary basis for professional standards of practice. The chapter introduces three ethical perspectives, including deontology (i.e., duty and fiduciary obligations), consequentialism (i.e., outcomes and broader welfare), and virtue ethics (i.e., character and integrity). The chapter discusses how these perspectives can be used to guide the day-to-day behaviors of financial advisors. The chapter introduces Johnson’s Five-Step Ethical Decision-Making Model, which translates theory into repeatable practices. The chapter concludes with a discussion of emerging challenges that will require firms and financial advisors to embed principled reasoning, testing, and monitoring into day-to-day decision-making.