The supply of entrepreneurship is a crucial factor in economic growth, although it is often overlooked in modern economic theory. The main reason for this oversight is that the theory is dominated by the model of perfect competition which, by assuming perfect knowledge, excludes any role for the entrepreneur. There may be imperfect knowledge of many things, including the qualities and prices of products, the qualities and price of factors of production, and technology. Whilst economic theory has given considerable attention to the first of these forms of imperfection, economists have done little about the other two. Yet all three are important in accounting for the role of the entrepreneur. In this book the author proposes two alternative models of entrepreneurial competition and discusses in detail the role of entrepreneurs and the factors influencing their supply. Harold Lydall is the author of The Structure of Earnings , A Theory of Income Distribution and Yugoslavia in Crisis .