A 2 X 2 X 2 factorial experiment was conducted with 128 growing-finishing steer calves to examine the effects of feeding whole v. rolled barley in diets containing either a constant proportion of concentrate (0-67) or proportionately 0-33 concentrate for 56 days followed by 0-90 concentrate for 83 days, with the concentrate being given at either 08.00 or 15.30 h. Steers given hay at 08.00 h and concentrate at 15.50 h grew proportionately 0-05 faster (P < 0-05) and had better dry matter (DM): gain ratios (P < 0-05) during the first 56 days than those given concentrate at 08.00 h and hay at 09.00 h. By the end of the trial steers fed at 15.50 h had similar daily gains to steers fed at 08.00 h but required proportionately 0-02 less DM : gain (P <0-05). No significant difference in gain was detected between steers given whole (1-30 kg/day) or rolled (1-38 kg/day) barley, but those given whole barley ate proportionately 0-08 more DM daily and had a proportionately 0-15 poorer DM : gain ratio (P < 0-05). The digestibility of diets containing whole grain was reduced (P < 0-05). Thirty-six steers given whole barley bloated compared with nine given rolled barley (P < 0-05). No significant differences were found either in DM intake or in final proportion of concentrate in the diet between steers given the diet containing proportionately 0-67 concentrate throughout the feeding period and those given the variable concentrate diets. There was a trend for DM: gain ratios to be poorer for steers given the constant proportion of concentrate (6-89 v. 6-65).