Forming implementation intentions ('If I encounter situation X, then I will perform behaviour Y!') increases the probability of carrying out goals. This study tested the hypothesis that mental imagery targeting key elements of implementation intentions further increases goal achievement. The residents of a student residence were assigned the goal of consuming extra portions of fruit every day for 7 days and randomly assigned to one of four conditions: control (active rehearsal), implementation intentions, goal intention mental imagery or mental imagery targeted to the implementation intentions. Among low fruit consumers, but not high fruit consumers, fruit consumption at follow-up was higher in the targeted mental imagery group than in the other group, with the lowest fruit consumption in the control group. The findings suggest that it may be beneficial to use targeted mental imagery when forming implementation intentions.