We provide the planner's solution to a model where households learn from exogenous natural disaster arrivals about arrival rates and spend to mitigate future damages. Mitigation cannot be decentralized due to positive externalities from curtailing aggregate risks. First-best can be implemented...

Aging populations in advanced economies are placing ever-increasing demands on government spending in the form of old-age benefits. Economies that have promised substantially more benefits than they have made provision to finance are heading into a prolonged era of fiscal stress. Unresolved...

International environment and development agencies increasingly emphasize external cofinancing when selecting projects to fund. This paper considers whether the emphasis on cofinancing helps promote institutional objectives, or creates perverse and inefficient incentives. We present a model of...

Poor water quality and sanitation are leading causes of mortality and disease in developing countries. However, interventions providing toilets in rural areas have not substantially improved health, likely because of incomplete coverage and low usage. This paper estimates the impact of an...

Cities generate negative, as well as positive, externalities; addressing those externalities requires both infrastructure and institutions. Providing clean water and removing refuse requires water and sewer pipes, but the urban poor are often unwilling to pay for the costs of that piping....

We study the extent to which collusion can explain the under-provision of clean sanitation technologies in developing countries. Using desludging services in Dakar as a case-study, we document that prices are 66% higher in areas where prices are likely coordinated by a large trade association,...

We study a growth model with an environmental asset which is a source of utility and an input to consumption and production. The stock of this asset follows its own ecological dynamics, which are affected by economic activity. We study the implications of an approach to ranking sequences of...

Over the past decade, non-Paris Club creditors, notably China, have become an important source of financing for low- and middle-income countries. In contrast with typical sovereign debt, these lending arrangements are not public, and other creditors have no information about their magnitude. We...