Purpose: We sought to determine whether participants in the Program of All-Inclusive Care for the Elderly (PACE) with an informal caregiver have a higher or lower risk of nursing home admission than those without caregivers. Design and Methods: We performed a secondary data analysis of 3,189 participants aged 55 years or older who were enrolled in 11 PACE programs during the period from June 1, 1990 through June 30, 1998. Cox proportional hazard models determined whether having any caregiver, as well as specific caregiver characteristics, such as either living separately from the enrollee, being over the age of 75 years, providing personal care, not reducing or quitting work to provide care, or not being a spouse, predicted time to nursing home admission. Results: Fewer than half of the participants (49.4%) lived with a caregiver, and 12.4% had no caregiver. Individuals who lived with their caregiver were frailer than either those who lived separately or those without a caregiver. We measured frailty in terms of functional and cognitive status, incontinence, and multiple behavioral disturbances. The presence of a caregiver did not change the risk for institutionalization. None of the caregiver characteristics were associated with a higher risk of nursing home admission. Implications: Unlike individuals in the general population, participants in PACE who lack an informal caregiver are not at higher risk of institutionalization. Further research is required to ascertain whether PACE's comprehensive formal services compensate for the lack of informal caregiving in limiting the risk for institutionalization. (Contains 3 tables.)