Research summary: This study employs longitudinal multilevel modeling to re‐examine the relative importance of business unit, corporation, industry, and year effects on business unit performance. Total variance in performance is partitioned into stable variance and dynamic variance. Sources of these two parts of variance are explored. Empirical results indicate that (1) stable effects of corporation‐industry interaction are substantially important, but were unequally confounded with stable effects of business unit, corporation, and industry in results of previous studies; (2) stable effects of corporation, industry, and corporation‐industry interaction, taken together, are of similar relative magnitude to stable effects of business unit; and (3) random and nonlinear year effects are very important in explaining dynamic variance. These findings extend our theoretical and empirical understanding of performance variability. Managerial summary: Whether stable or changing, business units themselves, corporate‐parents, and industries influence business unit operations. This article investigates the relative effects of these factors on business unit performance. Although the traditional wisdom is that business unit is critical, this research finds that corporate‐parent, industry, and interactions between these, taken together, are as influential as business unit. Specifically, interactions between corporate‐parent and industry are important for over‐time average business unit performance, indicating that a given corporate‐parent unevenly influences its business units in different industries and that a particular industry unevenly influences business units within itself from different corporate‐parents. This study also demonstrates that changes in business unit, corporate‐parent, and industry are important drivers of over‐time volatility of business unit performance and that effects of these changes differ. Copyright © 2016 John Wiley & Sons, Ltd.