For professional school counsellors who work in secondary schools, ethical issues arise more often than in other practice settings. While ethical codes and guidelines provide guidance in decision making, a reliance on ethical principles may still leave professionals open to criticism since such principles can be interpreted to suit the situation. Research in ethical decision making in psychology has proposed and tested a variety of constructs that influence ethical decisions. The Koocher and Keith-Spiegel (KKS) (2008. Ethics in psychology and the mental health professions. New York: Oxford University Press) model is grounded in moral cognitive theory and is a well-established practice-based model that provides a step-by-step process for examining a situation. However, the potentially complex legal and ethical dilemmas faced by school psychologists stem not only working with minors but also with other stakeholders including parents, teachers, school administrators, and community members. In this paper, I argue that depending on the moral intensity of the issue, a KKS (2008. Ethics in psychology and the mental health professions. New York: Oxford University Press) step-by-step approach has limitations in complex and dynamic environments, such as secondary schools. Therefore, I propose that two other ethical decision-making models supplement the KKS.