We examine characteristics of the 400 wealthiest individuals in the United States over the past three decades as tabulated by Forbes Magazine, and analyze which theories of increasing inequality are most consistent with these data. The people of the Forbes 400 in recent years did not grow up as advantaged as in decades past. They are more likely to have started their businesses and to have grown up upper-middle class, not wealthy. Today's Forbes 400 were able to access education while young, and apply their skills to the most scalable industries: technology, finance, and mass retail. Most of the change occurred by 2001.

Theoretical work on the principal-agent problem in financial contracting focuses on the conflicts of interest between an agent / entrepreneur with a venture that needs financing, and a principal / investor providing funds for the venture. Theory has identified three primary ways that the investor / principal can mitigate these conflicts - structuring financial contracts, pre-investment screening, and post-investment monitoring and advising. In this paper, we describe recent empirical work and its relation to theory for one prominent class of principals venture capitalists (VCs). The empirical studies indicate that VCs attempt to mitigate principal-agent conflicts in the three ways suggested by theory. The evidence also shows that contracting, screening, and monitoring are closely interrelated. In screening, the VCs identify areas where they can add value through monitoring and support. In contracting, the VCs allocate rights in order to facilitate monitoring and minimize the impact of identified risks. Also, the equity allocated to VCs provides incentives to engage in costly support activities that increase upside values, rather than just minimizing potential losses. There is room for future empirical research to study these activities in greater detail for VCs, for other intermediaries such as banks, and within firms.