Franziska Völckner and coauthors Chenming Peng, Tammo H.A. Bijmolt and Hong Zhao present a meta-analysis on brand extension success. Drawing on a large database of 2,134 effect sizes from research spanning 1990–2020, they examine the effects of parent brand equity and extension fit on extension success through a meta-analysis to develop empirical generalizations. The results show that parent brand equity and extension fit positively influence extension success. However, the multifaceted dimensions of these two drivers have differential effects. Furthermore, the authors provide a comprehensive analysis of moderators, namely, contextual factors (parent brand, extension, communication, and consumer factors) and research method factors. https://journals.sagepub.com/doi/abs/10.1177/00222429231164654).