These two volumes present empirical studies that have permanently altered professional debates over investment and productivity as sources of postwar economic growth in industrialized countries. The distinctive feature of investment is that returns can be internalized by the investor. The most straightforward application of this idea is to investments that create property rights, but these volumes broaden the meaning of capital formation to include investments in education and training. Postwar US Economic Growth traces the outstanding postwar performance of the US economy to investments in tangible assets and human capital. This volume provides the starting point for a new consensus on policies to generate growth by stimulating and rewarding investments. These policies will focus on returns that can be internalized by investors, ending the fruitless search for "spill overs" that can generate substantial growth without providing incentives for capital formation.