This study examined the effectiveness of the after-action review (AAR)-also commonly termed debrief-and 4 training characteristics within the context of Villado and Arthur's (2013) conceptual framework. Based on a bare-bones meta-analysis of the results from 61 studies (107 ds [915 teams and 3,499 individuals]), the AAR leads to an overall d of 0.79 improvement in multiple training evaluation criteria. This effect is larger than some of the largest training method effects reported in Arthur, Bennett, Edens, and Bell (2003), and it is also larger than Tannenbaum and Cerasoli's (2013) estimate of the effect of the AAR on task performance (d = 0.67). Two training characteristics consistently contributed to the effectiveness of the AAR: (a) alignment to the individual or the team, and (b) objective performance review media. The effects of the other training characteristics were often interactive. Most notably, the facilitation approach contributes to the effectiveness of the AAR in combination with the individual versus the team and the type of review media, with the most effective combinations being the self-led facilitation approach coupled with a team-aligned AAR, and the self-led approach coupled with objective media. Additionally, the AAR that is highly structured is more effective than a less structured AAR in the military, but high and low structured AARs display comparable effectiveness in healthcare. Overall, this study suggests that the effectiveness of the AAR should be understood as a function of the combined influence among multiple interacting characteristics. Future theoretical development and research should be directed at better understanding these interactions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).