This chapter is mainly concerned with the foster family as a system. The adult members are invited to consider, amongst other things, their own attachment history and some of the ways in which it might have bearing on their present parenting of their own children and their future work as foster parents. While there is general acceptance of the idea that foster parents’ experiences of their own childhood and parenting is likely to affect their approach to fostering significantly, it is not always obvious what sense to make of the account they offer. The nature of the interaction between a fostered adolescent and children of the family appears to have an important influence on whether the placement is experienced as safe enough for the adolescent to explore new ways of functioning. If a family has a permeable boundary, its members are likely to be more involved with other systems: school, work, church, friends and neighbours, and their own extended family.