This paper studies the efficient agreements about the dependence of workers' earnings on employment, when the employment level is controlled by firms.The firms' .superiorinformation about profitability conditions is responsible for this form of contract governance.Under plausible assumptions, such aj^reements will cause employment to diverge from efficiency as a byproduct of their attempt to mitigate risk.ll is shown that, if leisure is a normal good and firms are risk-neutral, employment is always ahoue the efficient level.Such a one-period implicit contracting model cannot, therefore, be used to "explain" unemployment as a rational byproduct of risk sharing between workers and a risk-neutral firm under conditions of asymmetric information.

[Social decision mechanisms that admit dominant strategies and result in Pareto optima are characterized by the class of mechanisms proposed by Groves. The concept of decision mechanisms is generalized and the characterization is shown to extend to these cases.]

This paper is concerned with tax policies designed to obtain an improved competitive allocation in the presence of consumption externalities. It is known that the full optimum can, in general, be attained only through the imposition of excise taxes at different levels for different individuals. Since these may be ruled out (possibly because of implementation costs), one is confined to consider second-best taxes. The common interpretation of the Pigouvian principle has called for taxes on the externality-creating commodities. With no relationships between the consumption of different commodities the Pigouvian principle is obviously impeccable. But the existence of substitutes or complements for an externality-causing commodity raises the possibility of indirect policies: treating the externality through the markets for related goods. Obviously, if the direct policy is not feasible, the indirect treatment may provide some partial remedy. We show, however, that even when direct policies are available, the overall optimum may involve only indirect policies. An example with such a result is provided in the paper. We also list a number of cases in which the traditional prescription is confirmed, and the overall optimum involves only direct policies.

I. A model of financial equilibrium, 412.—IL Effects of changes in the profit tax rate, 418.—III. Effects of changes in the taxation of retained earnings, 423.—IV. The nonneutrality of the corporate income tax, 427.—V. Conclusion, 430.

Our tax system was designed for an economy with little or no inflation. The current paper shows that inflation causes capricious changes in the effective rate of tax on capital income and therefore in the real net rate of return that savers receive. This is not only a temporary disequilibrium effect but one which persists in steady-state equilibrium. Unlike earlier papers by Feldstein and by Green and Sheshinski, the current study recognizes that firms finance investment by both debt and equity in a ratio that depends on the tax rates and on the rate of inflation.