Research Summary: Despite a plethora of studies, the moderating effects of contingency factors regarding the relationship between corporate planning (CP) and organizational performance (OP) remain open to discussion. Our meta-analysis analyzes 183 independent study samples, 84 of which are examined for the first time. We expand on previous meta-analyses by correcting for measurement error and dichotomization, and we use moderation analyses and meta-analytical regressions to explain heterogeneity in these studies. We find evidence for the moderating effects of task interdependence and uncertainty avoidance as contingency factors. Unexpectedly, we identify an interaction of the measurements of OP and CP with uncertainty avoidance. Our results provide new insights into the relationship between CP and OP. Management Summary: Managers who may doubt whether planning is still fruitful in turbulent times obtain a clear answer from our study: Yes, it is. CP is definitely correlated with OP. The effect sizes are stable over time and for different types of planning. However, the effect of CP on performance depends on the organizational context. Manufacturing firms benefit more than nonmanufacturing firms, and larger firms benefit more than smaller firms. Organizations in countries with high uncertainty avoidance show larger effects in relation to those in countries with low uncertainty avoidance. Finally, organizations facing high environmental uncertainty show higher effects of CP than organizations in more stable environments. However, the identified effects are conditional on the type of measurement of performance and CP.