The purpose of this study is to investigate how public leaders affect the commitment of subordinates to mission changes. To that end, we used a survey to analyze the commitment of followers to mission changes in a semipublic organization; namely, a municipal utility provider that had been recently forced to make substantial changes to its mission statement. Our findings, which are based on a sample of 278 respondents, indicate that transformational leaders can increase the commitment of their followers to mission changes by fostering perceived organizational support (POS) and by motivating their subordinates to engage in behavior that proactively promotes change. Multi-group analyses, as well as the analysis of comments supplied by the respondents to the survey, suggest that two factors influence particularly the ability of transformational leaders to increase their followers’ commitment to change: union membership and the length of the work relationship between followers and leaders.