This chapter presents a concise analysis of the main characteristics and changes in the aviation sector, mainly from the supply side, which has followed the deregulation.1 The aim is to draw a new profile of the airline industry in terms of new airline business models and compare their characteristics in a way which has rarely been presented in the literature to date. Section 2.2 describes the deregulation of the EU aviation market and part of the relevant literature. The discussion mainly concerns its effects on the airlines’ strategies and how they have consequently reorganized their models. In Sect. 2.3 these new models are described, with particular emphasis on network, pricing, and alliances. These three elements are discussed more in-depth in Sects. 2.4, 2.5 and 2.6, respectively. Section 2.7 concludes thisanalysis and introduces Parts II and III of this study.