The introduction and cultivation of new marine finfish in the Mediterranean aquaculture industry has been recently recognised as one of the most important strategies for the diversification of final products as well as the market relief from the competition among Mediterranean countries. Especially for Greece, this is imperative since it is the leading producer of European sea bass and gilthead sea bream in Europe today, with approximately 30,000 t annually. The National Centre for Marine Research, has focused its research on the cultivation technology of new species, their nutritional requirements, their pathology and the production of suitable fishfeeds. The main species now under research are red porgy, Pagrus pagrus and common dentex, Dentex dentex. Research on porgy has focused on the embryology and the study of the mass mortalities observed during the first days after hatching while for the snapper, on the nutritional requirements for the elimination of the cannibalism.