A review of the relevant literature suggests that limited research concerning siblings in foster care reflects a general lack of attention by any discipline to sibling relationships. Professional interest in siblings is growing, however, due to smaller nuclear families, the broader focus of the literature on sibling separations, and adoptees' sensitizing others to the importance of preserving relationships with biological kin. In the sociological literature, the 1980's have seen renewed interest in sibling placements. LePere and others (1986) report the adoption experiences of large sibling groups. Penelton (1982), Depp (1983), Kaufman et al. (1981), and Ward (1984) advocate for joint placements and recognition of sibling ties, and Timberlake and Hamlin (1982) apply the theoretical literature concerning siblings to problems of working with children in placement. Legal concern about separation of siblings in foster care arises in the context of changes in juvenile court practice that focus on safeguarding children's rights and on meeting their needs for stable relationships in substitute care. Although both legal and social work professions give high priority to maintaining sibling relationships in placement, social workers are more likely to give weight to relational factors that may undermine the positive effects of a joint placement. 45 references.