This article argues that environmental regimes entailing considerable administrative discretion are now serving to contextualise and partly to constitute property rights in English law. In particular, rights to use land are democratised' to varying degrees through the administration of environmental regulation, and are adapted to land-use problems on an evolving basis. In return, property rights affect environmental regulation, through legal protections for property interests, although the nature of the discretion exercised within environmental regimes seems to determine the kind and extent of this symbiotic influence. As a result, environmental law challenges property scholars to reflect on the impact of administrative decision-making on property rights, conceptually, doctrinally and in terms of its legitimacy. At the same time, environmental lawyers need to take seriously the nature and legal treatment of property rights in the application and analysis of modern environmental law.