This dissertation contains three studies. Chapter 2 investigates interactions between antitakeover provisions and managerial ownership, two corporate governance mechanisms. Antitakeover provisions weaken the incentive effect of managerial ownership and magnify its entrenchment effect, and thus will decrease the effect of managerial ownership on firm value. I show that the value effect of managerial ownership crucially depends on the strength of antitakeover provisions. For firms with weak antitakeover provisions, managerial ownership enhances firm value, unless managers have very high ownership. For firms with strong antitakeover provisions, however, increasing managerial ownership always destroys firm value. Also, managerial ownership sig...