I assess how employee involvement programs affect union commitment attitudes. Analysis of 229 survey responses indicates that participation attitudes have no effect on union commitment levels; previous participation has a positive effect; and organizational commitment has a negative effect. A similar pattern was observed on four subscales of union commitment: union loyalty, responsibility to the union, willingness to work for the union, and belief in unionism. I thank the employees, the unions, and the company at which this study was conducted. Also, I am grateful to suggestions and comments made by participants in the American University Department of Management Research Series. Finally, a word of thanks to Tom Case, Gordon Henry, David Jacobs, and Tom Vonk for their comments on earlier drafts of this paper.