Records of 377 heifers, randomly sampled from sires in three lines of Hereford cattle selected for weaning weight, yearling weight, or muscling score, were studied. Heifers were fed for 252 days postweaning, slaughtered and carcass data obtained to provide information on correlated response to selection. Phenotypic trends of line-year means indicated age adjusted rate of gain increased as did the percentage of weight adjusted retail product and bone while fat trim percentage decreased. Expected correlated responses were estimated from paternal half-sib heritabilities and genetic correlations and from regressions of offspring traits on midparent selection differentials. Selection for weaning weight, yearling weight or muscling score increased carcass weight, ribeye area and fat thickness, but decreased marbling. Carcass composition was affected by selection but changes were small. In data, adjusted to a constant age, where carcass weight increased, percentage of retail product and bone decreased while fat trim increased. In data, adjusted to a constant weight, the opposite trends occurred.