We use firm and chief executive officer (CEO) characteristics motivated by optimal contracting theory to estimate optimal CEO relative debt-equity incentive ratios. Equity values rise as firms adjust CEO incentive ratios toward their predicted optimums, whether that increases or decreases the relative incentive ratio. Debt values rise as firms adjust ratios upward and do not fall as they adjust them downward. Our predicted optimums explain changes in equity and debt values better than a model in which firms simply match CEO inside debt-equity ratios to firm debt-equity ratios. The results suggest important cross-sectional differences in firms’ optimal inside debt policies.

We show theoretically that optimism can lead a risk-averse Chief Executive Officer (CEO) to choose the first-best investment level that maximizes shareholder value. Optimism below (above) the interior optimum leads the CEO to underinvest (overinvest). Hence, if boards of directors act in the interests of shareholders, CEOs with relatively low or high optimism face a higher probability of forced turnover than moderately optimistic CEOs face. Using a large sample of turnovers, we find strong empirical support for this prediction. The results are consistent with the view that there is an interior optimum level of managerial optimism that maximizes firm value.