This paper argues that the personal interview method is particularly appropriate for the kind of exploratory and complicated theory-building research that ethical decision-making, as a topic, represents at present. In doing so, it examines the key tasks of the ethics researcher, the suitability of interviews for obtaining the kind of data needed to accomplish these tasks, and the ensuing problems faced by the interview methodologist. It concludes with suggestions for enhancing the validity and reliability of interview-based ethics research.