Ninety-six pure-bred Large White pigs weighing 80 to 100 kg were either not transported or transported for eight. 16 or 24 hours, and then either slaughtered immediately on arrival at the abattoir or kept in lairage for six hours before being slaughtered. The pigs travelling for eight. 16 or 24 hours lost 2.2, 2.0 and 4.3 per cent of liveweight, respectively, and the pigs travelling for 24 hours lost 2.6 per cent of hot carcase weight Both liveweight and hot carcase weight recovered during the lairage period although there was a net liveweight loss in comparison with the control animals. Only transport for 24 hours led to losses in carcase weight The concentration of non-esterified fatty acids increased with the time spent travelling. The concentrations of cortisol, creatine phosphokinase and lactate were all low in comparison with the levels found in commercially slaughtered animals. Plasma albumin and protein concentrations indicated that the animals were becoming dehydrated during the longer joumeys. The animals lay down for most of the journey and appeared to be asleep. During the period in lairage, the animals transported for eight hours had two distinct periods of feeding and drinking but spent most of the time lying down, but those transported for 16 and 24 hours showed far more eating and drinking acdivi. All the groups appeared tired, but the urge to eat of the groups transported for 16 hours, and especially 24 hours appeared to be more important There were behavioural and the physiological differences between the transported groups and the controls. Six hours in lairage with access to food and water allowed most of the physiological parameters to return to pretransport levels.