A calf's previous experience may be expected to influence its subsequent response to acute stress. In the present study, the effects of the social environment on the response to transport have been investigated. Direct behavioural observations of all competitive interactions were recorded for 40 h in a group of 18 3-month-old Friesian male calves reared in an intensive barley beef system. Butts, head-to-head battles, approach and avoidance behaviour and displacement of one calf from the trough by another were noted. The interactions of each calf with all 17 others were scored in a matrix according to wins and losses. Calves were then ranked according to the mean proportion of wins and clear social order was found at this point in development of the group. At 14 weeks of age, these calves were transported in a trailer in two groups of nine animals, for a distance of 4 miles. Blood samples were taken for cortisol analysis before and after transport. All calves showed a significant increase in cortisol levels in response to handling and transport. Calves which won least in social interactions had the highest basal cortisol levels and showed the greatest cortisol response following handling and transport. Calves winning most showed the smallest cortisol response to the procedure. These results suggest that a calf's response to handling and transport can be affected by its position in the social order. Changes in stereotypies associated with tethering of dairy cows I. Redbo Department of A nimal Nutrition and Management, Swedish University of Agricultural Sciences, Kungsangen Research Farm, S-753 23, Uppsala, Sweden