Since the last few years of the 1910s, the information contained in the pages of the Financial and Societies Anónimas, published in Madrid under the direction of Emilio Ríu, was regularised and, in the initial volumes of the s, a theoretically adjusted profile of those companies registered as Shared Companies. In addition to a nominal list of these, the Yearbook also systematised a count of some management boards, and sometimes their declared profits. Our purpose in this communication is to put forward some interim reflections on Madrid’s socio-economic fabric at the specific juncture of the post-war Europe, based on the view that the company is seen as an indicator of dynamism and a driver for change in structures. We are also not unaware of the possibilities for limitations or shortcomings of this material, as well as the need to be extended as far as possible with documentation from the Trade Register.