This volume contains the Proceedings of the Third International Conference on Copepoda, held at the British Museum (Natural History) in London during August 1987. The central theme of the conference was the biology of marine planktonic copepods, although the scientific programme was extremely varied reflecting the wide range of life styles adopted by copepods. The three invited symposia held during the conference focussed attention on particular topical areas of research within the field of marine plankton, and also provided reviews of chosen aspects of copepod biology. These symposia were highly successful. The papers they contained were both informative and stimulating and they bring to this volume a lasting significance. Each symposium was organised by its chairman; Bruce Frost (University of Washington) decided on the balance of topics, selected the speakers and introduced the session on 'The biology and taxonomy of Calanus', Roger Harris (Marine Biological Association) performed the same vital role for 'Experimental studies: rate processes in field populations of planktonic copepods', and Howard Roe (Institute of Oceanographic Sciences) for 'Oceanic and deep-sea copepods'. The impact of these papers will be much enhanced by the large number of high quality contributed and poster papers on marine plankton and by the invited review of 'Copepod luminescence' by Peter Herring (Institute of Oceano graphic Sciences). The fascinating review of 'Copepod eyes' by Mike Land FRS (University of Sussex) is not published here."