• Responses to cardiologists' and psychiatrists' recommendations for drugs and diagnostic actions were compared in a retrospective study of 788 consultations. Variables significantly related to outcomes achieved by cardiologists and psychiatrists were identified; similarities among these variables were evident only for the drug recommendations. Cardiologists' recommendations achieved a higher rate of concordance than psychiatrists' for both drugs and diagnostic actions. For drug recommendations, the interservice discrepancy in concordance was directly related to differences in timing of the consultations and incidence of recommendations to start a drug. For diagnostic recommendations, however, the difference was directly related to the consultants' service. The following factors may explain the less favorable outcome for psychiatrists' diagnostic recommendations: (1) the reasons for seeking psychiatric consultation, (2) the consultees' expectations, and (3) the skill of the psychiatrists in offering these recommendations.