Academic institutions and journals worldwide expect the research conducted by people in the life sciences, and, increasingly, the work of people in the humanities and social sciences, to be approved by an ethics board. Even if such approval is not required by a researcher's institution or research-site institution, one's target journal will usually require an explicit description of how the research was ethically conducted and the informed consent of participants obtained. For language teachers who conduct research, recruitment of one's own students into a research project is common. The author presents a case study of teacher research among nursing graduate students in an ESP foreign language classroom in Taiwan to highlight the ethical challenges faced by researchers who recruit their students as research participants.