The book presents a theoretical discussion about the measurement and management of organizational complexity, as well as an empirical study about the impact of organizational complexity on organizational performance. The prominent postulates given by Ashby and Luhmann - organizations should enhance or reduce organizational complexity to cope with growing complexity in the business environment - are discussed and tested empirically in this book. The empirical study support Ashby's assumption the organization should enhance organizational complexity in regard to market-driven complexity. A positive relationship between market- driven organizational complexity and organizational performance is confirmed. In contrast to the theoretical assumption that this relationship would vary between different levels of market-driven organizational complexity, no significant differences are found. Furthermore, a Structural Equation Model confirms the multi-dimensionality of the complexity construct. Thus, it is argued that researchers should not limit their models to one overarching complexity indicator, but should rather incorporate multiple drivers.