Management innovation entails the introduction of new-to-the-firm changes in management structures, processes, and practices intended to improve organizational functioning. We draw on relational demography theory to elucidate how behavioral dispositions stemming from top management and middle management similarity in professional characteristics (functional background and educational level) and biodemographic characteristics (age and gender) may facilitate management innovation. We argue that while a throughput functional orientation of top management can be expected to stimulate management innovation, greater similarity between top and middle management will strengthen the association between top management throughput orientation and management innovation by (1) engendering consistency in behavioral expectations between the managerial echelons and (2) motivating middle management to engage in extrarole behaviors. We test our theory on a sample of more than 8,000 top and middle managers in a cross-section of 33 organizations from 2000 to 2008 and adopt a novel content analysis-based measure of management innovation. We find compelling support for the moderating influence of professional similarity between top and middle management but uncover more complex patterns for cross-echelon similarity in biodemographic characteristics. We discuss implications for understanding the role of managers in management innovation, joint consideration of top and middle management characteristics in organizational change processes, the interplay between various types of innovation, and the measurement of management innovation. Promising future research directions are suggested.