Without appropriate genetic management of aquaculture stocks, founder effects, inbreeding, etc. can significantly reduce aquaculture performance. Properly planned management can prevent inbreeding and improve performance via selective breeding and other genetic techniques. Our research in this area covers a wide variety of species and countries, from carps in Asia to seabream in the Mediterranean and halibut in Scotland. A key theme common to much of this research is the application of microsatellite markers as "genetic tags", allowing the identification of families and pedigrees within hatchery stocks. Traits of interest include growth rate, disease resistance and colour. Studies of the taxonomy and genetics of wild species of potential interest to aquaculture dovetail into this area.