The aim of this research is to examine the generality of the part-set cueing eect, a well-known memory-inhibition phenomenon in basic research, to professional problem diagnosis. Three experiments were conducted. Experiment 1 examines whether part-set cueing aects the ability of auditors to recall diagnoses, and if so, whether memory inhibition is aected by the plausibility of the hypotheses. Experiment 2 examines whether the part-set cueing eect is sensitive to changes in the symptoms that drive the diagnosis and whether dierences in inhibition occur because of prompt plausibility or because of target plausibility. Experiment 3 extends the ®ndings of the ®rst two experiments to hypothesis generation and discriminates between competing accounts for the part-set cueing eect. The results show that part-set cueing eects occur during hypothesis generation and that they are robust to changes in the symptoms. However, the results from the experiments reveal an asymmetric inhibition eect. Inhibition is signi®cant when prompts contain low plausibility hypotheses that are also high in severity. When prompts consist of high plausibility or low severity hypotheses, no inhibition is observed. These ®ndings are considered to be consistent with an editing account of the part-set cueing phenomenon. The implications of these ®ndings to problem diagnosis and decision aids are discussed. Copyright # 1999 John Wiley & Sons, Ltd.KEY WORDS diagnosis; hypotheses generation; output interference; part-set cueing; problem solving One puzzle presented by basic memory research is the part-set cueing eect. The eect refers to a decrease in memory performance for items from a given set when other items from the set are provided, ostensibly as external cues (Nickerson, 1984). This ®nding is replicated in many experiments involving recently studied lists (e.g. Basden, Basden and Galloway, 1977;Parker and Warren, 1974; Roediger, 1978;Roediger, Stellon and Tulving, 1977;Slamecka, 1968Slamecka, , 1975 as well as in studies involving retrieval from long-term memory (e.g. Brown, 1968;Karchmer and Winograd, 1971; see Nickerson,