BACKGROUND: The quality of the relationship between patient and medical staff is crucial in oncological settings. We have developed and validated a short, self-administered questionnaire to measure patients' satisfaction with their relationship with the physician: the Patient-Physician Relationship Index (PPRI). MATERIALS AND METHODS: Content validity was evaluated by a two-stage (development and judgment) process. One hundred and nine cancer patients with metastatic disease were assessed during the second cycle of chemotherapy and 59 were reassessed eight weeks later. Quality of life and anxiety and depression were also evaluated. RESULTS: The PPRI is monofactorial. Cronbach's alpha coefficient was 0.81. Sensitivity to change was shown by the correlation with changes in patients' conditions. The PPRI scores were only weakly correlated with the majority of the EORTC and HAD subscale scores. CONCLUSION: The PPRI is an easy-to-use, self-administered questionnaire, developed in a population of patients with advanced cancer. It has good internal consistency and sensitivity to change