In an integrated group housing system for sows, animals of all stages of production are kept in one group, except around farrowing, and remain there throughout their productive life. Lactating sows have access to the suckling section of the house via an electronic gate. Jostling of piglets from different litters is avoided by keeping the litters in their own suckling pen until weaning. The system allows lactating sows to freely evade their piglets, and move between the suckling section and the communal area. They can maintain their social position and cool off in the relative cool communal area. Earlier observations (Houwers et al., 1992) showed sows decreased sucklings and increased their absence from the farrowing pen towards weaning. It was not clear whether the overall performance of the piglets was depressed by absence of sows before weaning. The relevance for practical farming partly depends on the production results that can be achieved.