Objectives: Compare care demands, strain, and health across 912 primary and secondary caregivers of parents, other family, and friends aged 50 and older. Methods: Data came from the nationally representative Caregiving in the U.S. 2015 data set. Two by three factorial ANOVAs and binary logistic regression examined the effects of primary caregiver status and relationship type on care demands and well-being. Results: Primary caregivers provided more hours of care for a longer duration and were more likely to report financial stress, and that caregiving made their health worse. Primary caregivers did not differ from secondary caregivers in emotional stress, and physical strain was comparable in primary and secondary caregivers of parents and other family. Caregivers of parents generally reported the highest levels of demands and stress/strain. Controlling for amount of care provided attenuated some of these differences. Conclusions: Secondary caregivers provide less care but report emotional stress comparable to primary caregivers. Primary caregivers of friends provide high levels of assistance that may increase their physical strain. Clinical Implications: Caregiver research and intervention should include greater attention to needs of secondary caregivers, and caregivers of friends, and ways to strengthen their potentially critical roles.