This qualitative study examines the role of older people (60 years and above) in fostering decisions for orphans and non-orphans within extended families in a rural Ugandan community heavily affected by HIV. Fieldwork conducted in 2006 provided information on the influence of HIV on fostering decisions through 48 individual in-depth interviews and two group interviews with foster-children and family members to develop detailed case studies related to 13 fostered adolescents. The adolescents included five non-orphans and eight orphans (five were double orphans because they had lost both parents). Older people play a very important role in fostering decisions as potential foster-parents, advisers, mediators and gatekeepers. They have a high level of authority over the foster-children, who are regarded as important resources within the extended family. With fewer potential caregivers available because of HIV-related deaths, the responsibility for fostering orphans has often fallen to surviving older people. Fostering is used by older people and the child's extended family as a strategy to ensure the welfare of the foster-child. When the foster-parent is an older person, it is also used to ensure physical and emotional support for the older person themselves. Support from the extended family towards foster households is widely reported to have been reduced by HIV by diminishing resources that would otherwise have been made available to support foster care. New initiatives and investment are required to complement community and family resources within well-managed social protection and welfare programmes. To be effective, such programmes will require adequate investment in administrative capacity and monitoring. They must aim to strengthen families and, recognizing that resources are limited, should prioritize the community's poorest households, rather than specifically targeting households with orphans or other foster-children.