OBJECTIVES: To study the ethical reasoning of nurses and physicians, and to assess whether or not modified focus groups are a valuable tool for this purpose. DESIGN: Discussion of cases in modified focus groups, each consisting of three physicians and three nurses. The discussion was taped and analysed by content analysis. SETTING: Five departments of internal medicine at Danish hospitals. SAMPLE: Seven discussion groups. MAIN MEASUREMENTS: Ethical content of statements, style of statements, time used by each participant. RESULTS: Danish physicians (...) and nurses do not differ in the kind of ethical reasoning they use, but physicians use more of the discussion time than nurses, they use a more assertive style of argumentation, and the solutions chosen are usually first put forward by physicians. CONCLUSION: The results and informal comparisons with similar data from long qualitative interviews indicate that groups of this kind are a useful tool for gathering data on ethical reasoning. (shrink)