A continuous video recording of the behaviour of sows and their piglets was made from before farrowing until 48 h after the birth of the last piglet. Ten litters, receiving chopped straw bedding daily, were compared with 10 litters in unbedded farrowing crates under similar housing and management conditions. Provision of straw had no significant effect on farrowing duration, which was very variable, or on piglet survival and growth rate. Sows made more major posture changes (transitions between standing, sitting and lying) in the early stages of farrowing (median 4, 2, 0 for inter-birth intervals 1, 2 and 3+ respectively). This tended to be more marked in the absence of straw bedding (19·5 versus 5 major movements in the first three inter-birth intervals, P = 0·07, and 4·5 versus 2 transitions between sternal and lateral recumbency, P = 0·07). Early born piglets took longer to find the udder (45, 21, 11 min for piglets 1, 2 and 3 respectively) with no significant effect of straw provision. The inter-birth interval increased towards the end of farrowing and more stillbirths occurred. In the 48 h after farrowing sows without straw made more major posture changes (2·0 versus 1·4/h, P = 0·05) and also tended to make more transitions between sternal and lateral recumbency (0·8 versus 0·6/h, P = 0·06). Piglets without straw spent more time in the heated forward creep box (29 versus 4%, P < 0·01). There was no significant effect of straw on the time piglets spent on the udder (39 versus 44%), the frequency of cyclical suckling (1·3 versus 1·5/h) or the time spent active (42 versus 45%).