This chapter examines the complex interplay of ethical and clinical considerations in psychotherapy, research, and supervision with sexual and gender minority (SGM) clients. Using ethical codes and “best practices” documents from mental health organizations throughout the Anglophone world, the authors explore topics such as clinical competence, nonmaleficence, non-discrimination, confidentiality, multiple relationships, using and conducting research, financial matters, advertising, assessment and diagnosis, and supervision through a feminist, queer lens. Ethical considerations are illuminated through brief vignettes grounded in affirmative clinical practices and a cultural humility approach.