Over the past couple of decades, differentials in the level of private contributions to charitable organizations have become a central matter of public policy. Because private charitable contributions finance many socially valuable activities (for example, education and the arts), many governments have tried to boost private philanthropy through various active policy interventions. Furthermore, the temptation to rely on private contributions to finance the provision of public goods has increased substantially in recent years as fiscal constraints have become tighter. Yet there is little...