This essay provides introductions to five of the major topics to do with the history of the theory of production and the theory of the firm. The first chapter is an introduction. The second considers the change from a normative approach to the theory of production to a largely positive approach. Before, roughly, the 17th century the main approaches to the theory of production were normative. The third looks at the relationship (or the lack of a relationship) between the division of labour and the theory of the firm. Even today the mainstream of economics does not emphasise the division of labour in the theory of the firm. In the fourth chapter, the development of the proto-neoclassical approach to production is examined. The development of theories of monopoly, oligopoly and perfect competition as well as the theory of input utilisation are discussed. The fifth chapter looks at Marshall’s idea of the representative firm. This was the main early neoclassical approach to the theory of industry-level production. Marshal wished to be able to construct an industry supply curve without having to assume all firms were identical. The sixth examines the challenges to the neoclassical model in the period 1940-1970. The last chapter is a short conclusion.