Proceedings of the Fourth International Marine Biological Workshop, April 1989. Contains 63 papers dealing with many aspects of the taxonomy, ecology, behaviour, morphology and physiology of local species and with the effects of pollution upon them and their importance as biofoulers. A special section is devoted to Hoi Ha Wan, a coral-fringed bay at the entrance to Tolo Harbour, which is being proposed as Hong Kong's first marine reserve.