Worldwide, there is a growing expectation that teachers will act in a ?professional? manner. Professionalism, in this regard, includes identification of a unique body of occupational knowledge, adherence to desirable standards of behaviour, processes to hold members to account and commitment to what the profession regards as morally right or good. In other words, as ethical conduct. Teaching ethically involves making reasoned decisions about what to do in order to achieve the most good for learners. Often, this involves a complex (...) interplay between current context, past experience and personal beliefs and values. However, teacher education and accountability frameworks typically give priority to the ?practical rationality? of planning, delivery and assessment of the official curriculum, not the ?value rationality? involved in exploring the ethics of teaching in difficult practical circumstances. An aspirational code of ethics for teachers was recently developed by the New Zealand Teachers Council. The authors were part of a group commissioned to design and deliver a single professional development workshop for teachers to raise awareness about the code. This article focuses on the challenges of developing a workshop that both informs and educates teachers about ethics. (shrink)