The principal objective of this book is to bring about a better scientific understanding of biodiversity, which is an essential prerequisite for its efficient and rational use. The book constitutes papers from an International Forum held in Paris in September 1994 organised by the International Union of Biological Sciences (IUBS). It addresses one of the key concerns of the Convention of Biological Diversity, adopted by the 1992 United Nations Conference on Environment and Development (UNCED), namely the general lack of information and knowledge regarding biodiversity, and the urgent need to develop scientific, technical and institutional capacities to provide the basic understanding upon which to plan and implement appropriate measures.