The authors identify the fundamentals behind the dynamics of the U.S. stock market over the past 30 years. They specify a structural vector-error-correction model following the methodology of King, Plosser, Stock, and Watson (1991). This methodology identifies structural shocks with the imposition of long-run restrictions. It allows the authors to calculate an equilibrium measure of stock market value based on the permanent components of the time series. A better understanding of the components that drive stock market movements could provide insight into the potential effects of the recent technological revolution on the dynamics of the stock market's equilibrium value, as suggested by Hobijn and Jovanovic (2001).