Within a rational general equilibrium model in which agents care only about personal consumption, we consider a setting in which, due to borrowing constraints, individuals endowed with local resources underparticipate in financial markets. As a result, investors compete for local resources through their portfolio choices. Even with complete financial markets and no aggregate risk, agents may herd into risky portfolios. This yields a Pareto‐dominated outcome as agents introduce “community” risk unrelated to fundamentals. Moreover, if some agents are behaviorally biased, or cannot completely diversify their holdings, rational agents may choose more extreme portfolios and amplify the effect.

This article explores the information effect of financial risk management. Financial hedging improves the informativeness of corporate earnings as a signal of management ability and project quality by eliminating extraneous noise. Managerial and shareholder incentives regarding information transmission may differ, however, leading to conflicts regarding an optimal hedging policy. We show that these incentives depend on the accounting information made available by the firm. Under some circumstances, if hedge transactions are not disclosed (i.e., firms report only aggregate earnings), managers hedge to achieve greater risk reduction than they would if full disclosure were required. In these cases, it is optimal for shareholders to request only aggregate accounting reports.

We develop an agency model of financial contracting. We derive long-term debt, a line of credit, and equity as optimal securities, capturing the debt coupon and maturity; the interest rate and limits on the credit line; inside versus outside equity; dividend policy; and capital structure dynamics. The optimal debt-equity ratio is history dependent, but debt and credit line terms are independent of the amount financed and, in some cases, the severity of the agency problem. In our model, the agent can divert cash flows; we also consider settings in which the agent undertakes hidden effort, or can control cash flow risk.

Agency problems limit firms' access to capital markets, curbing investment. Firms and investors seek contractual ways to mitigate these problems. What are the implications for investment? We present a theory of a firm's investment dynamics in the presence of agency problems and optimal long-term financial contracts. We derive results relating firms' investment decisions, current and past cash flows, firm size, capital structure, and dividends. Among the results, optimal investment is increasing in current and past cash flow; and optimal investment is positively serially correlated over time (after controlling for investment opportunities). These results hold for a range of agency problems.

We characterize equilibrium leverage dynamics in a trade‐off model in which the firm can continuously adjust leverage and cannot commit to a policy ex ante. While the leverage ratchet effect leads shareholders to issue debt gradually over time, asset growth and debt maturity cause leverage to mean‐revert slowly toward a target. Investors anticipate future debt issuance and raise credit spreads, fully offsetting the tax benefits of new debt. Shareholders are therefore indifferent toward the debt maturity structure, even though their choice significantly affects credit spreads, leverage levels, the speed of adjustment, future investment, and growth.

We analyze the optimal trading and ownership policy of a large shareholder who must trade off diversification and monitoring incentives. Without commitment, the problem is similar to durable goods monopoly: the share price today depends on expected future trades. We show that the large shareholder ultimately trades to the competitive price‐taking allocation, even though it entails inefficient monitoring. With continuous trading, the large shareholder trades immediately to this allocation if moral hazard is weak enough that her private valuation of a share is decreasing in her stake. Otherwise, the large shareholder adjusts her stake gradually. We consider implications for asset pricing, IPO underpricing, and lockup provisions.

A privately informed seller seeks to liquidate a portfolio to raise cash. Each asset’s liquidity thus depends on the impact of its sale on the value of the entire portfolio. We demonstrate the importance of cross-signaling and derive sufficient conditions for a liquidity “pecking order” that determines the order of sale. For assets backed by a common pool, liquidity naturally aligns with seniority. Finally, we extend the portfolio liquidation game to consider security design and demonstrate the optimality of pooling securities and selling senior tranches or debt secured by the pool, with retention increasing in asset quality or informational asymmetry.

We study an impatient, risk-neutral government that cannot commit to a particular debt path, financed by competitive lenders. In equilibrium, debt adjusts slowly toward a debt-to-income target, exacerbating booms and busts. Strikingly, gains from trade dissipate when trading is continuous, leaving the government no better off than in financial autarky, owing to a sovereign “debt ratchet effect.” Moreover, citizens who are more patient than their government are strictly harmed. We characterize equilibrium debt dynamics, ergodics, and comparative statics when income follows a geometric Brownian motion and analyze devices that allow the sovereign to recapture gains from trade.

Self-regulation is a feature of a number of professions. For example, in the U.S. the government delegates aspects of financial market regulation to self-regulatory organizations (SROs) like the New York Stock Exchange and the National Association of Securities Dealers. We analyse one regulatory task of an SRO, enforcing antifraud rules so agents will not cheat customers. Specifically, we model contracting/enforcement as a two-tier problem. An SRO chooses its enforcement policy: the likelihood that an agent is investigated for fraud and a penalty schedule. Given an enforcement policy, agents compete by offering contracts that maximize customers' expected utility. We assume that the SRO's objective is to maximize the welfare of its members, the agents. We show that the SRO chooses a more lax enforcement policy—meaning less frequent investigations—than what customers would choose. A general conclusion is that control of the enforcement policy governing contracts confers substantial market power to a group of otherwise competitive agents. We also investigate government oversight of the self-regulatory process. The threat of government enforcement leads to more enforcement by the SRO, just enough to pre-empt any government enforcement.

We consider the strategic timing of information releases in a dynamic disclosure model. Because investors don't know whether or when the firm is informed, the firm will not necessarily disclose immediately. We show that bad market news can trigger the immediate release of information by firms. Conversely, good market news slows the release of information by firms. Thus, our model generates clustering of negative announcements. Surprisingly, this result holds only when firms can preemptively disclose their own information prior to the arrival of external information. These results have implications for conditional variance and skewness of stock returns.