This experimental study concerned the effects of repeated students' evaluations of teaching coupled with collaborative consultation on professors' instructional skills. Twenty-five psychology professors from a Dutch university were randomly assigned to either a control group or an experimental group. During their course, students evaluated them four times immediately after a lecture (class meeting in which lecturing was the teaching format) by completing the Instructional Skills Questionnaire (ISQ). Within 2 or 3 days after each rated lecture, the professors in the experimental group were informed of the ISQ-results and received consultation. Each consultation, three in total, resulted in a plan to improve their teaching for the next lectures. Controls received neither their ISQ-results nor consultation during their course. Multilevel regression analyses showed significant differences in ISQ-ratings in the experimental group compared to the control group, specifically on the instructional dimensions Explication, Comprehension and Activation. In addition, the impact of each of the three consultations plus differences between targeted versus non targeted dimensions were analyzed. This study complements recent non-experimental research on a collaborative consultation approach with experimental results in order to provide evidence-based guidelines for faculty development practices.