Study the evolution of international environmental law

International environmental law is a set of rules and regulations of international law governing the relations between followers and actors of international law including governmental and non-governmental laws in order to protect environment as well as it is an emerging field whose turning point was Stockholm Conference in 1972. Since then, this field has undergone many changes and lawyers have divided the path evolution into three stages: the 1972 conference, the 1992 Rio Conference and the Rio + 20 Conference; these developments are mainly focused on issues such as development of preventive measures, extend the guarantees of governments' environmental commitments, adjust governments will and curtail national sovereignty principle. However, the process has faced obstacles and limitations such as lack of financial resources, environmental issues and national preferences and governance. Strong and efficient international institutions should be established that have necessary competence and ability in advancing environmental objectives in order to accelerate this process.