The 34th European Marine Biology Symposium was held in Ponta Delgada, The Azores, between 13th and 17th September 1999. It was organised by the University of the Azores in association with the Municipal Museum of Funchal (Madeira), and the Plymouth Environment Research Centre (University of Plymouth, UK). The selected topics, dictated by the position of the Azores in the Atlantic Ocean, were: `Ecology and Evolution on Island Shores', `The Open Ocean', and `The Deep Ocean'. Each topic was introduced by a recognised expert of international reputation and these keynote reviews provide authoritative summaries of the current status of these very important topics in marine biology. The 35 papers which make up this volume bring new ideas and concepts relating to the functioning of marine systems extending from the intertidal, through the pelagic realm down to the deep sea. The book covers many aspects of the biology of marine organisms and will have wide interest to all those interested in the life of the world's oceans.