This book represents the Proceedings of the 37th European Marine Biology Symposium, held in Reykjavik, Iceland, 5-9 August 2002. The main themes of the symposium were Migrations and Dispersal of Marine Organisms. These themes are highly relevant today. There is widespread man-aided dispersal (e.g. by ballast water) of marine plants and animals, which may have substantial effects on the regions receiving new species. The new introductions may result in reduced diversity of plants and animals and may affect natural resources in the countries receiving toxic algae and other foreign elements....