The conservation of biological diversity was first identified as a priority in 1972 at the United Nations Conference on Human Environment in Stockholm. Throughout the rest of the 1970s, many international and regional legal instruments on particular aspects of biological diversity were adopted, including: i) The 1971 Ramsar Convention on Wetlands, which seeks to protect these biologically prolific but undervalued ecosystems. ii) The 1973 Convention on International Trade in Endangered Species of flora and fauna (CITES), which bans or regulates trade in 3500 plant and 4000 animal species through a system of permits and certificates. iii) The 1979 Bonn Convention on Migratory Species (CMS), which coordinates regional and global efforts to protect some 10,000 migratory species, including birds, dolphins, and marine turtles. Despite these efforts, it became apparent in the 1980s that the loss of biodiversity was still accelerating. In May 1988, UNEP established an Ad Hoc Working Group of Experts on Biological Diversity with a mandate to prepare an international legally binding instrument for the conservation and sustainable use of biological diversity. In 1991, the Ad Hoc Working Group evolved into an Intergovernmental Negotiating Committee (INC) which held seven sessions to negotiate and adopt the text of the Convention on Biological Diversity. The Convention on Biological Diversity is the most important of all the international agreements on biodiversity. Negotiated under the auspices of UNEP, the Biodiversity Convention was opened for signature in June 1992 at the ‘Earth Summit’ held in Rio (the United Nations Conference on Environment and Development), and entered into force in December 1993. 175 countries have now ratified, or acceded to, the Convention, with the USA being a notable exception.