【正文】 across ?rms that are subject to the same taxation rates. Empirical evidence from the United States (Copeland and Weston, 1992) shows that the capital structure of corporations did not change much after corporate ine tax came into existence. In Australia, where there is no dual ine taxation at all, capital structure is roughly the same as in other economies (Rajan and Zingales, 1995). Booth et al. (2020) found that the tax bene?ts vary in developing countries and play no role in the determination of capital structure choice. . Agency Theory and Capital Structure Even if markets are perfect and there is no tax impact, agency theory suggests that the appropriate mix of debt and equity is still an important matter for corporate governance. In general, debt claims provide the holders with a ?xed repayment schedule but little in the way of rights to control the pany, as long as the repayment schedule (and sometimes certain other terms) is met. However, creditors can have a strong in?uence over a pany if it gets in ?nancial distress but, even if a pany is ?nancially sound, creditors can in?uence whether it can obtain additional funding for proposed new projects. For example, a bank that has loaned a pany the money for factory expansion can make it easy or hard for the pany to borrow more money for a new o?ce building. Conversely, equity claims – in particular, mon stock – give shareholders the right to vote for Boards of Directors and on other important corporate issues such as major mergers or plans that would dispose of substantial portions of the pany?s assets. Shareholders are also entitled to receive dividends or other distributions whenever the pany pays them or, if the pany is liquidated, to receive the assets of the pany after paying all debts and any securities, such as preferred stock, that rank ahead of mon shares. These two features, the right to vote and the right to receive dividends and other distributions, are the de?ning characteristics of mon shares. Jensen and Meckling (1976) identify two potential sources of con?ict. On the one hand, con?icts between debtholders and equityholders arise because the debt contract gives equityholders an incentive to invest suboptimally. More speci?cally the debt contract provides that, if an investment yields large returns well above the face value of the debt, equityholders will capture most of the gain. If, however, the investment fails, debtholders bear the consequences because of limited liability. As a result, equityholders may bene?t from ?going for broke?。 . investing in very risky projects, even if they are valuedecreasing. Such investments result in a decrease in the value of the debt. The loss in value of the equity from the poor investment can be more than o?set by the gain in equity value captured at the expense of debtholders. Equityholders correctly anticipate equityholders? future behavior. In this case, the debtholders receive less for the debt than they otherwise would. Thus, the cost of the incentive to invest in valuedecreasing projects created by debt is borne by the equityholders who issue the debt. This e?ect, generally called the asset substitution e?ect, is the agency cost of debt ?nancing. On the other hand, con?icts between shareholders and managers arise because managers hold less than 100% of the resid