We empirically evaluate the job performance effects of a 6 month part-time training program in a large retailchain, in which participants received feedback on their training success based on a final exam. The data'squasi-experimental structure allows comparison of sales revenue of trained and untrained managers before,during and after the training. We find that the training significantly increases sales of very successfulparticipants by approximately 8% during and by 7% after the training period. However, the training has asubstantial negative impact on the post-training sales performance of unsuccessful participants. The resultsindicate that the indirect motivational effects of training programs may be much more important than thedirect effects of skill acquisition.