The differential effects of 2 forms of feedback on energy consumption behavior were examined in 2 units of a metallurgical company. In 1 unit, employees received information about energy conservation, had to set goals, and received feedback on their own conservation behavior. The same procedure was followed with employees in a 2nd unit, but they also received information about the performance of the 1st unit. In accordance with predictions from social identity theory and social comparison theory, the results clearly showed that employees in the comparative feedback condition saved more energy than employees who only received information about their own performance, even half a year after the intervention. A remarkable finding was that behavioral change took place with hardly any changes in attitudes or intentions. The discussion focuses on these findings and on their implications for organizational behavior change in general.