The subject of this thesis is the commodification of knowledge and information, as an ever more present practice in the world and as a cause that leads to their growing unavailability. Commodification of knowledge and information in a broad sense is understood as transformation of knowledge and information into commodities. The aim of this thesis is to analyze the key elements that lead to commodification in a material and a theoretical sense, such as profit, business ecosystems, intellectual property, etc. The key prerequisite of commodification are precisely material conditions, especially within the area of business, which turns workers into workers of knowledge, while the knowledge and the information they have are seen as a kind of intellectual capital. Material aspect aside, commodification also happens under theoretical trends within science, which view knowledge from a "pragmatic" point of view, for which it is typical to regard knowledge and information within the framework of utility and applicability. That framework is largely motivated by an excess of value and improving the company's business practices. Material conditions will be showcased through a short historical overview of the transformation of the area of business and other significant elements, the most prominent one being practices which condition dealing with knowledge. Theoretical hypotheses will be addressed with critical librarianship in mind, in order to clarify the main terms linked to commodification of knowledge and the theoretical practices that are closely connected to the problem of the commodification of knowledge and information. Finally, based on all of this, answers will be proposed to the question of how the commodification of knowledge influences its availability.