The invasive species problem will become increasingly important in the years to come. Trade, travel and tourism are rapidly globalized, and border controls are reduced. This affects natural ecosystems in which aggressive invaders may have disastrous effects. `New' diseases affect human, animal and crop health. The Convention on Biological Diversity presents national authorities with a tall order in coping with this problem. For the first time in one volume, this book presents both ecological, biological and epidemiological aspects of invasive species, as well as the problem of disease organisms for agriculture and human health. The book constitutes a comprehensive background to the global strategy for managing invasive alien species which now is being developed by SCOPE and UNEP. The book is well suited for management staff in various environmental, economic and social sectors. It is essential for university and college teachers, researchers in ecology, natural resources management, and social sciences, as well as M.Sc. and Ph.D. students.