The article describes the context for a major piece of interdisciplinary research undertaken in Ontario, Canada investigating whether the nature of ethical behaviour was changing over time: whether professionalism or profit was driving the behaviour of lawyers. The project had both conceptual and philosophical aspects and an empirical investigation. Previous research on professional ethics is canvassed, including studies of medical ethics, and the particular problems associated with research about the legal profession are identified. The full methodology of the empirical aspect of the research is described and all methodological decisions are discussed and justified. Appendices contain all research instruments. The results of a pre-test involving twenty lawyers demonstrated that better results were obtained through the use of anecdotes or critical incidents than through use of vignettes.