The forthcoming UK ban on stall and tether housing for sows will result in an increase in the use of group housing for these animals. In group housing systems, certain individuals may be particularly aggressive or bullied by others, and this may result in injury or socially induced stress. To attempt to overcome these problems we need to know the answers to questions such as whether removal of a particularly aggressive animal from a group will result in a general decrease in aggression, or whether it will simply result in other animals becoming more aggressive. Answers to these sorts of question require a fundamental understanding of pig social behaviour and individual characteristics. For example, is aggressivness a stable individual characteristic across time and situation? This research addressed these issues by examining the cross-time consistency of individual aggressiveness and social status in groups of pigs.