In 2005 the total world production of sea bass reached 80,000 tons. The estimated amount of feed used to support this production was 150,000 tons valued at about € 100 million. Notwithstanding the increase in production, producer’s profit margins are squeezed by i) the increase in price of feed ingredients, and ii) the decline/instability of fish prices. Feed costs account for up to 60% of total production costs and inappropriate feeding management can therefore be detrimental to farmer's profits. Optimal feed management includes the use of well balanced feeds covering the species’ nutritional and energy requirements and cost efficient feeding regimes. The large variation amongst generally poor industrial feed conversion ratios (FCR) obtained in European sea bass farming is a clear indication of inappropriate feeding. This project is a joint effort between European aquaculture stakeholders targeting the accurate determination of the basic nutritional requirements of sea bass throughout the production cycle and best practices in feeding regimes and technology in order to achieve a significant reduction in production FCR values. Specifically, the optimum dietary protein and energy levels which are crucial parameters for effective feed formulation will be determined for European sea bass and evaluated on the farm using the latest demand feeding technology. These requirements will be studied in relation to the main influencing biotic and abiotic factors which are fish size, diet composition, feeding level and frequency, water temperature and oxygen levels. The cost efficient use of diets with formulations targeting the specific seasonal and developmental needs of the fish will effectively improve production FCR and have a significant economic benefit for aquaculturists. Optimising feed utilization efficiency, fish growth, health and welfare besides promoting production efficiency and economy will also have a significantly positive environmental impact.