Stearns for their helpful comments. We also thank Sarah Leonard for her assistance in data collection. Finally, we acknowledge the financial support for this project provided by the Anderson Graduate School of Management at the University of California, Riverside and the Amos Tuck School at Dartmouth College.Drawing on work from behavioral learning theory in psychology, this study examines the influence of prior organizational acquisition experience on the performance of acquisitions. This theory, which examines both the conditions preceding organization events and organizational responses, predicts that experience effects may range from positive to negative. Consistent with this theory, data from 449 acquisitions show an overall U-shaped relationship between organization acquisition experience and acquisition performance. In addition, the more similar a firm's acquisition targets are to its prior targets, the better they perform. These findings suggest that relatively inexperienced acquirers, after making their first acquisition, inappropriately generalize acquisition experience to subsequent dissimilar acquisitions, while more experienced acquirers appropriately discriminate between their acquisitions. Behavioral learning theory, then, may enhance understanding of organization experience effects.'The vast majority of research on organization experience adopts a learning-curve perspective that predicts positive returns to experience. This work has been restricted, however, to the narrow context of manufacturing settings, where gains in manufacturing experience are associated with decreases in unit costs (e.g., Yelle, 1979; Dutton, Thomas, and Butler, 1984). Outside manufacturing settings, however, the effects of organizational experience may be more difficult to predict, and studies have often produced contradictory results. This is particularly true of the effects of an organization's prior acquisition experience on an acquisition's subsequent performance. To extrapolate findings from manufacturing settings to such other organizational situations may be misleading to organization researchers because it assumes that manufacturing conditions are similar to other organizational conditions, and the positive effects of experience found in manufacturing contexts will also be found wherever organization experience is applied from one event to another. For acquisitions, however, the outcomes of organizational experience may depend on the similarity between past acquisitions and the present acquisition, which, in turn, could determine the appropriateness of applying or disregarding past acquisition experience in managing a new acquisition. Hence, experience with a dissimilar acquisition may not be relevant.We chose acquisitions as an appropriate context in which to study the effects of organizational experience for a number of reasons. First, a firm makes acquisitions that may vary from similar to dissimilar to previous acquisitions, which implies that there may be positive and negative effects of experience. Second, un...