In the fifty years that have lapsed since the adoption of the Antarctic Treaty (Washington, 1 December 1959), a wide-ranging scheme of environmental protection measures has been developed and consolidated for this fragile ecosystem. While environmental concerns were not highlighted between the principles and objectives initially included in the treaty, they were the object of a comprehensive and innovative system for protecting the environment drawn up only a few years later. The 1991 Protocol to the Antarctic Treaty created the first ever integrated system for environmental protection. The protocol is elaborated on and supplemented by its six annexes. How is this system articulated? What are its chief characteristics? How has it adapted to the Antarctic area’s new needs and its environs? How effective would it be in the event of an environmental emergency? These are a few of the questions that this article attempts to answer.