Information on patient satisfaction is considered a way of including patients' perspectives in the planning and assessment of services. The study of patient satisfaction is a relatively new field, and despite the surge in popularity and use of satisfaction measures during the past three decades, different issues remain to be explored. This is not meant to dissuade clinicians from using satisfaction measures, but rather to allow them to proceed in a thoughtful way, recognizing what these measures can reasonably show us about patients' perceptions of the care and treatment interventions they receive. The proposed approach to classifying the characteristics of patient satisfaction measures should help to highlight potential reasons for variation in results when satisfaction measures perform differently and will be of value if it increases the specificity with which clinicians select measures to achieve their purposes.