Tax expenditures, credits and guarantees, and other nonconventional expenditures are prominent features of the public finances of the United States and other industrialized democracies. While reliable data on these practices have generally been available only for a decade or less, there is reason to believe that these types of transactions now constitute a larger share of total public expenditure than they did in the past. This article discusses the concepts arid implications of two types of nonconventional expenditures—tax expendituures and loans—as well as recent efforts to bring them within the scope of the budget process. The article deals mostly with American practices, but it also draws on the experiences of other democratic countr