It is generally assumed that a well-developed market for corporate control results in a takeover threat that disciplines management. We study the effects of a larger market for corporate control and show that an increase in the number of potential raiders of a firm may decrease the probability of a takeover. In turn, the weakened takeover threat results in weaker managerial incentives. In equilibrium, this implies lower managerial effort and therefore a lower ex ante value of the firm. (c) 2006 Elsevier B.V. All rights reserved.