The Family Pen System is alternative housing system that has emerged in an attempt to balance the production and ethological aspects of pig husbandry. It is based on the models of natural behavior of pigs. After farrowing the sows stay within the individual pen and after five weeks they move with their offspring to the family group with the boar. The piglets grow up in social stable group and remain with the sows another two months. Under these conditions, piglets are gradually weaned and continue to the feeding period in the same group, thus there is virtually no weaning stress, which is one of the critical stage in the current pig husbandry. At the same time the reproductive performance of sows is not drastically reduced, as the lactating sows, under specific management, gradually enter to the lactational oestrus and are mated by the boar. This alternative housing system was originally designed by Alex Stolba and experimentally proved in Fibl. However, there has not been a large expansion into practice. We can see it at the Biofarm Sasov, where the system has been used and improved over the course of fifteen years so that it can work in the long term.