This book offers a new slant on the relations between warfare and state construction. Historians looking at how war funding impinged on state development, and how state growth made wars more demanding affairs, have tended to downplay the role of military provisioning entrepreneurs. Written off as corrupt and selfish, these entrepreneurs conflicted with the received view of a rationally growing and modernizing state. This book (or the Spanish case during the eighteenth century) shows that the state-entrepreneur relationship was much more fluid and constant than previously thought. The state was not able to enforce a top-down military supply policy; at the same time it benefited from the entrepreneurs collaboration and their shared mercantilist ambitions. The entrepreneurs mobilization of Spains military supplies was crucial for extending state authority and helped to knit together national and colonial markets. However, the fluid state-entrepreneur relationship gradually became shrouded in privileges and monopolies, not so much driven by ideology or imposed by the entrepreneurs, but rather as an arrangement exploited by the state to boost its control over them, whittling down middlemen and ensuring the solvency and creditworthiness of the chosen few. This arrangement spiralled into a risky interdependence and cramped entrepreneurial competition. The book furnishes new insights into the role of military entrepreneurs in debates about warfare and state construction.