The traditional approach which the economical theory has given to the company has been from within the function of production and its derivatives, the function of costs, in order to subsequentlysituate it in market structures with perfect or imperfect competition, to be able to recognize its behaviour towards prices, regardless to whether they take these latter or they fix them. The situation teaching faces once the students in the classroom come from business administration, industrial economy, financial engineering, or accounting is to manage to correctly articulate what the economical theory says, with company problems on the short and long runs. Working this relation expounds serious difficulties that were not unfamiliar to the classical economists nor to those of nowadays. This article aims at introducing what has been said bythe economists who have mostly been interested in this issue; and at producing some reflections and suggestions for teaching – the learning of the economical theory for the aforementionedstudents, an outcome of the work undertaken in the subject General Economy in the University of Medellín. In economical History, the distinction between a capitalist and an enterpreneur has not alwaysbeen clear because of the emphasis set on the triad: capital, work, and land. When Walras introduces the landlord, this latter is an artifactor of reasoning rather than a nuclear element. Schumpeter is interested in innovation: this creating creation-destruction bi-polarity. The neo-institutionalists found an interstice to enter the firm: the costs of transaction. It seems as though the interprise were a “black safe” for the economist, who knows what comes in and out of it, but not what happens inside it.