This paper conducts a comprehensive study of the optimal exercise policy for an executive stock option and its implications for option cost, average life, and alternative valuation concepts. The paper is the first to provide analytical results for an executive with general concave utility. Wealthier or less risk-averse executives exercise later and create greater option cost. However, option cost can decline with volatility. We show when there exists a single exercise boundary, yet demonstrate the possibility of a split continuation region. We also show that, for constant relative risk averse utility, the option value does not converge to the Black and Scholes value as the correlation between the stock and the market portfolio converges to one. We compare our model's option cost with the modified Black and Scholes approximation typically used in practice and show that the approximation error can be large or small, positive or negative, depending on firm characteristics.

We derive the optimal labor contract for a levered firm in an economy with perfectly competitive capital and labor markets. Employees become entrenched under this contract and so face large human costs of bankruptcy. The firm's optimal capital structure therefore depends on the trade‐off between these human costs and the tax benefits of debt. Optimal debt levels consistent with those observed in practice emerge without relying on frictions such as moral hazard or asymmetric information. Consistent with empirical evidence, persistent idiosyncratic differences in leverage across firms also result. In addition, wages should have explanatory power for firm leverage.