We propose a clarification of the notion of a soft budget constraint, a concept widely used in the analysis of socialist, transitional, and market economies. Our interpretation is broad enough to embrace most existing approaches to soft budget constraint phenomena and provides a classification...

We argue that when discoveries are "sequential" (so that each successive invention builds in an essential way on its predecessors) patent protection is not as useful for encouraging innovation as in a static setting. Indeed, society and even inventors themselves may be better off without such...

We argue that when externalities such as pollution are nonexcludable, agents must be compelled to participate in a "mechanism" to ensure a Pareto-efficient outcome. We survey some of the main findings of the mechanism-design (implementation-theory) literature -- such as the Nash implementation...