In a study of how physicians evaluate patient compliance, practitioner judgments were compared to the self-reports of 138 adult patients receiving treatment for pulmonary diseases at an outpatient clinic. The research found no significant relationship between physician evaluations of compliance and accounts given by the same patients. The conclusions of physicians regarding patient compliance proved to be influenced by their views on the seriousness of the condition and the effectiveness of treatments, but patient reports were different. Physicians clearly have difficulties in appraising the compliance behavior of their patients.