This thesis focuses on "access to the network of medicines" and aspires to present the author's research on the basic question: is the circulation of medicines included in essential facilities networks? And if so, what is the structure and function of this "network"? What are its imperfections? and finally, how individuals, producers, wholesalers, doctors, pharmacists and consumers interact as individuals within the network and interact with each other in order to access the "characteristic supply", i.e. the "medicine". The dissertation follows a "circular" methodology, starting with the description of the concept of "medicine" and all its legal bases, continuing with the creation of the "characteristic" supply, then with the chain of successive transfers and ending with the actual description of the network, its autonomy, as reflected through the licensing system, but also its imperfections at national and Community level, integrating it finally into the doctrine of civil law and especially the law of obligations, general and specific. More specifically, starting from necessary and interesting historical references, which give a global view of the issue, the description of the “characteristic supply” follows. This is followed by an analysis of the precursor stage of creation of the characteristic supply, in order to understand its complexity, the patent factor inherent in the nature of the medicinal products, the precursor contracts (e.g. clinical studies and research) and the subsequent marketing authorization process, and transfers. Next, the investigation focuses on the sale starting from the "typical" sales contract, governed by the provisions of the Civil Code (513 et seq. CC), but finds that, especially for this provision, it is also designed outside the Civil Code and is referred to in the central regulatory legislation ND96/73 as a "special" sale. This is followed as alternative access, by the lease, understood as a concession of use and commercial exploitation of the "file" of the medicinal product (contractual license) and closes with the common consumer sale, the prescription as an extension as per article 876 of the Greek Covil Code and the influence of the third party (doctor) on the choice of provision, the role of the pharmacist and ultimately the price and the way it is formed. In all chapters, it uses references to comparative law, making the minimum necessary parallels, while for modern issues, still unregulated by special laws, supplementary analogous application of the provisions of the Civil Code is followed. Finally, the thesis examines and analyses all issues relating to breach of contract, negligence and liability that arise.