Reports an error in “Why and when hierarchy impacts team effectiveness: A meta-analytic integration” by Lindred L. Greer, Bart A. de Jong, Maartje E. Schouten and Jennifer E. Dannals (Journal of Applied Psychology, 2018[Jun], Vol 103[6], 591-613). In this article, the hierarchical form value for the study by Cantimur et al. (2015a) was incorrectly coded as representing ‘acyclicity’ rather than ‘steepness’. Updating the coding for this study means that there is just one acyclicity study in our dataset (Bunderson et al., 2016) rather than two, and resulted in some changes to the coefficients in our moderator model presented in Table 3. The corrected Table 3 is presented in the erratum. The only substantive change to our conclusions is that Hypothesis 4a, regarding the effects of membership instability, is no longer supported at p < .05. We also note a minor change to how Hypothesis 5b is tested–we can no longer test for the effects of acyclicity at the study level of analysis. However, we can still test this hypothesis using the 'shifting unit of analysis' approach. These analyses revealed that the population coefficient for acyclical hierarchies was unlikely to be different in magnitude from that of steep hierarchies or centralized hierarchies. Our original conclusion and interpretation–that Hypothesis 5b is not supported, but this interpretation is limited due to low sample size–remain intact. See erratum for full description. (The following abstract of the original article appeared in record 2018-03097-001.) Hierarchy has the potential to both benefit and harm team effectiveness. In this article, we meta-analytically investigate different explanations for why and when hierarchy helps or hurts team effectiveness, drawing on results from 54 prior studies (N = 13,914 teams). Our findings show that, on net, hierarchy negatively impacts team effectiveness (performance: ρ = −.08; viability: ρ = −.11), and that this effect is mediated by increased conflict-enabling states. Additionally, we show that the negative relationship between hierarchy and team performance is exacerbated by aspects of the team structure (i.e., membership instability, skill differentiation) and the hierarchy itself (i.e., mutability), which make hierarchical teams prone to conflict. The predictions regarding the positive effect of hierarchy on team performance as mediated by coordination-enabling processes, and the moderating roles of several aspects of team tasks (i.e., interdependence, complexity) and the hierarchy (i.e., form) were not supported, with the exception that task ambiguity enhanced the positive effects of hierarchy. Given that our findings largely support dysfunctional views on hierarchy, future research is needed to understand when and why hierarchy may be more likely to live up to its purported functional benefits. (PsycINFO Database Record (c) 2019 APA, all rights reserved)