The bruising of sheep carcases results in economic losses to the meat industry and is one indicator of welfare problems before slaughter. In this study the numbers of potentially bruising events and the transport conditions of sheep taken directly from farms to a slaughterhouse were related to the occurrence of bruising. Among 2509 sheep in 79 groups the mean number of potentially bruising events was 0.71 per sheep, and they were due mainly to riding behaviour and wool-pulls which occurred most commonly while they were being handled before being stunned. The mean proportion of bruised carcases per group was 0.25, and there was a mean of 0.31 bruises per sheep. Most bruises occurred on the back and were bright red and between 2 and 4 cm in diameter. The mean space allowance per animal on the vehicles was 0.29 m2 and the mean journey time was 251 minutes. A logistic model was used to examine the effects of seven variables on the risk of bruising. More space per animal, transport on the lower deck or at the front of the vehicle, and increased handling all increased the risk of bruising. There were some significant correlations between potentially bruising events and bruising on specific parts of the body.