The papers in Volume 28 of Tax Policy and the Economy illustrate the depth and breadth of the research by NBER research associates who study taxation and government spending programs. The first paper explores whether closely held firms are used as tax shelters. The second examines the taxation of multinational corporations. The third discusses the taxation of housing, focusing on the ways in which current income tax rules may affect location and consumption decisions and lead to economic inefficiencies. The fourth paper offers an historical perspective on the political economy of gasoline taxes, with a particular focus on the response to the oil shocks of the early 1970s. The fifth and final paper uses the tools of financial economics to estimate the unfunded liabilities of the Pension Benefit Guaranty Corporation.