We model the competition between digital forms of fiat money and private digital money. Countries digitize their currencies–by upgrading existing or launching new payment systems (including CBDCs)–to compete with foreign fiat currencies and private digital money. A pecking order emerges: less dominant currencies digitize earlier, reflecting a first-mover advantage; dominant currencies delay digitization until they face competition; the weakest currencies forgo digitization. However, delayed digitization allows private digital money to gain widespread adoption, eventually weakening fiat money’s role. We highlight how geopolitical considerations, stablecoins, and interoperability between fiat and private digital money shape the dynamics of currency competition.

We develop a dynamic contracting theory of asset- and cash flow-based financing that demonstrates how firm, intermediary, and capital market characteristics jointly shape firms’ financing constraints. A firm with imperfect access to equity financing covers financing needs through costly sources: an intermediary and retained cash. The firm’s financing capacity is endogenously determined by either the liquidation value of assets (asset-based) or the intermediary’s going-concern valuation of the firm’s cash flows (cash flow-based). The optimal contract is implemented with defaultable debt—specifically unsecured credit lines and senior-secured debt—and features risk-sharing via bankruptcy. When the firm does well, it repays its debt in full. When it does poorly, distress resolution mirrors U.S. bankruptcy procedures (Chapters 7 and 11). Secured and unsecured debt are complements because risk-sharing via unsecured debt increases secured debt capacity. Debt and equity are dynamic complements because future access to equity financing increases current debt capacity.

Private equity funds intermediate investment and affect portfolio firm performance by actively engaging in operational, governance, and financial engineering. We study this type of intermediation in a dynamic agency model in which an active intermediary raises funds from outside investors and invests in a firm run by an agent. Optimal contracting addresses moral hazard at the intermediary and firm levels. The intermediary's incentives to affect firm performance are strongest after poor performance, while the agent's incentives are strongest after good performance. We also show how financial engineering, that is, financial contracting with outside investors, interacts with operational and governance engineering.

We develop a model in which a start-up firm issues tokens to finance a digital platform, which creates agency conflicts between platform developers and outsiders. We show that token financing is preferred to equity financing unless the platform expects strong cash flows, has large financing needs, or faces severe agency conflicts. Tokens are characterized by their utility features, facilitating transactions, and security features, granting cash flow rights. While security features trigger endogenous network effects and spur platform adoption, they also dilute developers’ equity stake and incentives so that the optimal level of security features decreases with agency conflicts and financing needs.

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.

How much of a loan should a lender retain, and how do loan sales affect loan performance? We address these questions in a model in which a lender originates loans that it can sell to investors. The lender reduces default risk through screening at origination and monitoring after origination, but is subject to moral hazard. The optimal lender-investor contract can be implemented by requiring the lender to initially retain a share of the loan that it gradually sells to investors, rationalizing loan sales after origination. The model generates novel predictions linking loan and lender characteristics to initial retention, sales dynamics, and loan performance.