Frederic L. Pryor uses the concept of structural complexity to show how changes in the population, the labour force, the structure of industry, the financial system, foreign and domestic trade, and the government sector are related to the same general trend in the US economic system over the past forty years and in the coming twenty years. He also investigates the impact of these changes on the functioning of the system, exploring such matters as the long-term rising unemployment rate, the allegedly increasing volatility of the economy, the changing degree of competition, and the evolving economic role of the government. The discussion is aimed at those who wish to view the economy as a whole and who are concerned with problems of understanding an economy that is becoming increasingly complex along many different dimensions. For specialists a number of appendices discuss a variety of technical issues.