The "information explosion" which occurred in the field of environmental law during the past decade has long been recognized as a problem for international action. Following an initial pilot project for the compilation of data on environmental legislation, undertaken in 1971 at the initiative of Mr. Maurice Strong in the course of preparations for the Stockholm Conference (Third Session of the Preparatory Committee, A/CONF. 48/PC. III/CRP.13), UNEP, through its International Referral System, has provided support to automated data storage and retrieval experiments in this field, such as the "Environmental Law Information System" of the International Union for Conservation of Nature and Natural Resources (IUCN). While there is at present no international database ensuring reliable world-wide coverage of environmental law in general, important and environmentally relevant collections of sectoral legislation exist in several Specialized Agencies. Among these, the International Labour Organization (ILO) and more recently the International Atomic Energy Agency (IAEA) have developed computerized systems for legal data processing.