This chapter defines ethics as applied in the financial services profession. Specifically, ethics is presented as the norms and standards that sustain trust, market integrity, and client protection. The chapter begins with an insider-trading vignette to frame why ethical conduct goes beyond legal compliance. The chapter then describes the historical roots of modern practice. The chapter describes four core ethical principles: integrity, fairness, accountability, and transparency. The discussion continues by reviewing contemporary pressures that shape firm and financial advisor conduct. A special emphasis is given to technological innovations, including FinTech, blockchain, and AI, and the tensions these innovations create in relation to data privacy, algorithmic bias, inclusion, and cross-border oversight. To explain why misconduct persists, the chapter groups systemic, organizational, and individual factors into categories, including client vulnerability, product complexity, conflicts of interest, incentives, weak accountability, and inadequate training. The goal of categorization is to provide a clear foundation for ethical reasoning when providing financial services advice. The chapter concludes by connecting ethics principles to real-world situations and describing frameworks and tools that can be used to minimize client harm while fostering a firm culture of responsibility and compliance.