We analyze how the costs of smoothly adjusting capital, such as incentive costs, affect investment timing. In our model, the owner of a firm holds a real option to increase a lumpy form of capital and can also smoothly adjust an incremental form of capital. Increasing the cost of incremental capital can delay or accelerate investment in lumpy capital. Incentive costs due to moral hazard are a natural source of costs for the accumulation of incremental capital. When moral hazard is severe, delaying investment in lumpy capital is costly, and overinvesting relative to the first-best case is optimal. Received January 24, 2017; editorial decision March 15, 2019 by Editor Itay Goldstein.

We build a dynamic agency model in which the agent controls both current earnings via short-term investment and firm growth via long-term investment. Under the optimal contract, agency conflicts can induce short- and long-term investment levels beyond first best, leading to short- or long-termism in corporate policies. The paper analytically shows how firm characteristics shape the optimal contract and the horizon of corporate policies, thereby generating a number of novel empirical predictions on the optimality of short- versus long-termism. It also demonstrates that combining short- and long-term agency conflicts naturally leads to asymmetric pay-for-performance in managerial contracts.