In recent years, many firms have chosen to separate their CEO and board chair positions. Prior research has demonstrated that there are three forms that a CEO–board chair separation can take: apprentice, departure, and demotion. In this paper, we examine the antecedents of these three types. Our results show that the three types of separation each have different profiles in terms of the prior performance of the firm, the independence of the board, and the career horizon of the incumbent CEO. The findings in this paper provide unique insights into the factors that drive boards' structural choices. As questions about board leadership structure become more nuanced and more relevant in both scholarship and practice, a full understanding of these factors will only become more important. Copyright © 2013 John Wiley & Sons, Ltd.