The patient's failure to cooperate effectively in the patient/physician (patient and physician) interaction has been shown to be a problem of significant magnitude. In the present study, an attempt was made to identify specific, patient behaviors which might be related to physician judgment of a good patient and progress of treatment. A checklist of 37 behaviors was compiled. A series of 100 patients was observed during their interaction with physicians and occurrences of behaviors from the checklist were noted by an experimenter. Physicians also indicated whether the patient was considered to be a good patient and whether treatment was progressing as expected. For every third patient, physicians noted the occurrence of behaviors from the checklist. An association was found between some behaviors from the checklist and the physicians' judgment. There was also shown to be a difference in the ability of the experimenter and the physicians involved to detect these behaviors.