Decapod crustaceans are a particularly important animal group in a variety of aquatic environments, such as freshwater, estuaries, and oceans. Research on this group has increased during recent decades, and relates to their economic and ecological importance. The papers included reflect current trends in decapod crustacean research, and present results on a diversity of specific research fields, grouped into the major themes: a) Systematics, Phylogeny, and Biogeography, b) Growth, Morphology, and Development, c) Ecology and Behaviour, d) Reproduction, and e) Fisheries and Culture. The Colloquia Crustacea Decapoda Mediterranea are devoted to decapod crustacean research, and organised on a 3-year basis by institutions of the Mediterranean geographical area. The scope of these meetings has progressively widened throughout the sequence of events, and presently welcomes contributions from crustacean research world-wide.