In this important new book, Mark Casson argues that the fundamental significance of entrepreneurship requires it be fully integrated into core social science disciplines such as economics and sociology, as well as into economic and business history. This book shows how this can be done. It formalises the role of the entrepreneur as innovator, risk-taker and judgemental decision-maker, and relates these functions to the size and growth of the firm. Mark Casson discusses entrepreneurship as a form of strategic networking, showing how entrepreneurs gain access to established networks in order to source information, and then create their own networks to exploit this information. Applying these insights to historical evidence leads to a radical re-interpretation of key issues in economic and business history, including the emergence of trading companies, the spread of empires, the rise of the modern corporation and the globalisation of the firm.