An interactive decision support tool based on Multi-Criteria Decision Analysis (MCDA) can help health professionals integrate the principlist (principle-based) and casuist (case-based) approaches to ethical decision making in both their training and practice. MCDA can incorporate generic ethical principles as criteria; then draw on case-based reasoning as the basis for specifying, in the individual case, the available options, the ratings of each option on each criterion, and the relative weighting of the criteria. This produces a personalised, transparent and decomposable opinion on the merits of each option, as a contribution to enhanced deliberation. As proof of concept and method an exemplar aid adds veracity and confidentiality to beneficence, non-maleficence, autonomy and justice, as the criteria, with case-based reasoning supplying the necessary inputs for the decision of whether a nurse should disclose the poor prognosis of a patient to a close relative of the patient, when asked, on their first encounter.