The Control Preferences Scale is widely used in decision research to measure patient preferences for participation in treatment decision making with health care providers. Following anecdotal reports of confusion with the scale the authors conducted an exploratory interview study to examine perceptions of the meaning and applicability of the Control Preferences Scale for men with localized prostate cancer seeking treatment in a multidisciplinary urology clinic. The preliminary data suggest potential validity challenges when the Control Preferences Scale is used in a multidisciplinary prostate cancer care setting, including the clinical context of localized prostate cancer and the meaning of shared decision making.