The potential for aquaculture of the great scallop (Pecten maximus) is great due to increased fishing pressure on wild stocks and the consistent high value of the species. Research work in Europe has concentrated on improving the larval rearing techniques in the hatchery and for on-growing. In the grow-out phase the main constrains is the length of time to harvest (>5 years) which may be reduced through selection for increased growth rate in a well designed selective breeding program. The establishment of such a program requires methods for reliable production of a large number of full- and half-sib families, mating procedures to avoid selfing and thus inbreeding, technology for individual tagging of a large number of animals at an early age, and reliable estimates of genetic (co)variances for important economic traits like survival and growth. These objectives will be addressed by the PhD student (Tove Leren) for which we apply for funds, in addition to the funds made available by the ongoing Marie Curie project "Bivalves from Farm to Fork".