In this study, the origin and main parameters of the Essential Facilities Doctrine are analysed through the case-law that developed out of the application of the EC Competition Rules. Besides putting forward the historical roots, the basic criteria and limitations that apply to the Doctrine are elaborated so as to clarify the legal and analytical foundations of the Doctrine in the EU context. In addition, the added value attributed to the Doctrine in realm of competition policies pursued in network-based industries is expounded with special emphasis on telecommunications sectors. With this regard, the potential role of EFD against the challenging effects of &lsquo / convergence&rsquo / phenomenon and the technological changes is discussed. At last, the effects of EFD on the competitive dynamics of Turkish telecommunications sector which is undergoing a liberalisation process are also examined with the accompanied Turkish case-law.