The constraints upon the sow-piglet relationship differ markedly between husbandry systems. Within the farrowing crate the sow and the piglets are physically unable to remove themselves from one another. In most outdoor farrowing systems the sow must remove herself from her litter in order to feed and drink and, where piglets are successfully restrained within the farrowing hut, may spend a significant proportion of her time seperated from the litter. Frequently piglets are not successfully restrained and from the first week after farrowing will spend time following the sow. The aim of this experiment was to examine whether the constraints upon the access of the piglets to the sow in the neonatal environment effect the post-weaning behaviour of piglets.