Learners often insufficiently monitor their comprehension, which results in overconfident judgments of learning and underachievement. In the 3 present experiments, we investigated whether insufficient comprehension monitoring is due in part to the fact that learners are not sufficiently aware of the benefit of comprehension monitoring and thus scarcely engage in this process. As an intervention, we informed learners about the likely negative consequences of failing to monitor their comprehension. Specifically, we informed them about the high frequency of and the detrimental consequences that result from making overconfident judgments of learning. In Experiment 1 we found that for university students, this intervention increased their engagement in comprehension monitoring, led to more cautious judgments of learning, and fostered the acquisition of conceptual knowledge in a subsequent learning phase in which they received instructional explanations relating to a new topic. By contrast, this intervention was less beneficial for 13- to 15-year-old high school students: Although the intervention increased their comprehension monitoring and led to more cautious judgments of learning, it did not foster the acquisition of conceptual knowledge from the subsequent explanations (Experiment 2). In Experiment 3, we varied whether 13- to 15-year-old high school students received (a) information about the frequency of and the detrimental consequences that result from making overconfident judgments of learning and (b) information about effective regulation strategies. The results of this experiment suggest that the limited beneficial effect found in Experiment 2 could be attributed to a lack of knowledge regarding effective regulation strategies for this age group.