Although indispensable for long-term economic growth, organizational changes are usually met with resistance. This article draws on psychological theories and empirical evidence to highlight why and under what conditions changes lead to resistance and what likely consequences of resistance are. Furthermore, the article discusses the variables that have been identified as success factors for organizational change initiatives. These include individual difference variables and objective characteristics of the changes, but in particular aspects of the implementation, such as fairness and trust, adequate communication strategies, leadership, and participation. Finally, conclusions summarizing the most important aspects that are beneficial to consider in managing organizational change initiatives are presented.