1. Live-weight and carcass components of three strains of commercial turkeys were compared: males were slaughtered at fortnightly intervals from 12 to 24 weeks of age and females from 12 to 18 weeks.2. Age, live-weight and sex had major effects but, once these factors had been allowed for, little or no residual variation in the carcass components remained. For this reason the question is posed whether conformation per se has a major effect on yield.3. The study yielded data which should be of value in exercises attempting to optimise production systems.