Adjudication was used very rarely during the early development of international environmental law, with states preferring other mechanisms for resolving disputes over natural resources or transboundary pollution. This situation has changed substantially in recent decades and environmental matters are now routinely litigated in a growing array of international courts and tribunals. This chapter surveys the diverse and expanding opportunities for international environmental litigation, and assesses the various jurisdictional bases upon which environmental claims can be mounted. It is seen that the defining characteristic of adjudication in contemporary international environmental law is the operation of a largely uncoordinated patchwork of distinctive jurisdictions, several of which operate in competition with one another in addressing environmental disputes.

Adjudicating international environmental cases

The expanding jurisdictional patchwork

The first judicial engagement with international environmental disputes took place in several well-known arbitrations in the nineteenth and early twentieth centuries. These cases were conducted on an ad hoc basis in relation to specific controversies rather than on the basis of standing treaties dealing with environmental matters. Today the practice is far more varied, and there are four main ways in which environmental disputes may be brought before international adjudicative bodies. First, in a continuation of early practice, states may submit specific disputes, on an ad hoc basis, to arbitration or to judicial settlement by permanent courts and tribunals.