Following the liberalization wave in the airline sector, airports have been gradually taken out of the public sphere and open to the private initiative. This phenomenon is generally referred to as privatization, but not all the cases consist of, in fact, a full divestiture of assets. Although infrastructure construction, management and financing are undertaken by the private sector during a pre-defined period, usually 30 years or more, the property remains public or is transferred to the public domain after that period. This is a form of Public-Private Partnership (PPP) where two different models can be found: institutionalized PPP or a typical contractual regime, such as the concession arrangements. PPP options have been a "hot" topic over the last decade, being developed in several sectors, such as energy, water, road and seaports transportation infrastructures, etc, but few studies in the literature can be found on the PPP projects development in airport systems, for example, as far as risk-sharing is concerned. This paper looks at recent developments in airport "privatization" and "deregulation", distinguishing privatizations from PPP arrangements, through a case study approach, and establishing a comparative analysis of different PPP models used for airport management. Some comments are made about the Portuguese model and the announcement of future privatization.