This research note reports a confirmatory factor analysis for three of Perry's (1996) public service motivation (PSM) subdimensions: self-sacrifice, commitment to public interest, and compassion. A mail survey of national award-winning volunteers constitutes the sample. Results indicate strong support for Perry's instrument, most noticeably better results for self-sacrifice than those found in Perry's original exploratory work. Implications and recommendations for PSM instrument development are discussed. 10.1177/0734371X07309523