s of common action, while the setting of more precise rules and standards was the aim of the cooperation in the framework that has been created. The fact that international organizations, such as UNEP, play a growing role in the international legislative process is certainly one of the factors that has fostered this development.34
The drafting and the adoption of regional conventions following the same pattern makes it easier to adapt generally agreed upon principles and rules to specific conditions. In the field of the international protection of human rights, this is certainly the case and the regional seas programme of UNEP - which combines it with the technique of umbrella conventions completed by protocol - certainly corresponds to the requirements of realism and efficiency.
More and more often, the drafters of a treaty feel it necessary to provide for an easy updating of the instrument. This is due to the rapid progress in knowledge of the biosphere, its deteriorations, the new forms of pollution, and the new harmful substances that are destroying our planet. The most useful technique in this regard is the adoption of technical norms and specifications -e.g. a list of polluting substances or endangered species- in the form of annexes of the main treaty and of special procedures for modifying such annexes without being obliged to resume the traditional, slow procedure for the modification of treaties.35 This approach shows the intrusion in international law of a new element, the time factor, to which later developments will be devoted.
All these innovations show implications of global change for international law' even if in some cases the use of such new methods and legal techniques started at the end of the 1940s. However, new approaches mostly stem from the necessity to solve international environmental problems. They all seem to be a part of the fundamental changes that international lawyers have to accept. Indeed, they show a trend towards a legal system in which the intricate web of international relations, in a growing number of fields, must be more flexible. The whole evolutionary process shows the need to negotiate in order to solve problems, rather than to adopt strict rules, understanding that some fundamental principles and rules are to be defined by determining the goals and creating an adequate framework for action. Dynamism, i.e., the adaptability and openness for change, is also a part of the innovations: this might even be one of the major contributions of global change to the evolution of international law, since it places the whole legal system in a new perspective, that of time.
B. Implications of global change for the implementation of international legal rules
Another aspect of the functions of international law, on which global change certainly has an impact, is the implementation and the enforcement of international legal rules. Indeed, the new requirements modify the tasks of states, they make it necessary to use or to create new international mechanisms for the surveillance of the implementation of such rules and they change our approach to international liability.
Quite often, international treaty rules related to environmental protection constitute an intrusion into the traditional sphere of action of states: for example, control of industrial or other activities, surveillance of the state of the environment,36 control of the exportation and importation of substances such as chemicals, waste,37 or of parts or derivatives of protected specimens of wild flora and fauna,38 etc. In all these fields state authorities must intervene in order to implement the treaty obligations and quite often this means the adoption of specific regulations in national legal systems. In a way, one might speak of a non-self-executing provision, which can be implemented only if the national legislation has adopted corresponding measures. In some cases such measures entail the designation of authorities that can deliver permits39 or ensure the contact with other national authorities.40 In certain situations penal s