A code of ethics is a standard that governs and guides ethical behaviour of an organization towards its employees, and interactions between the organization and its external stakeholders. This publication is intended to explain the benefits for nuclear industry operating organizations of having a well functioning code of ethics, to propose areas that should be considered for inclusion in a nuclear industry operating organization’s code of ethics, and to explain how to develop, implement and sustain such a code. This publication is addressed primarily to senior managers of nuclear industry operating organizations and will prove useful to those in the nuclear industry that are establishing a code of ethics or benchmarking their existing practices.