Background and Objectives: Proxy decision-making may be flawed by inaccurate perceptions of risk. This may be particularly true when older adults are the targets of the decisions, given the pervasive negative stereotypes about older adults. Methods: In study 1, individuals aged 18- to 87 years (as target persons) as well as one of their close social partners (as informants) reported on the risks they perceived for the target person in various life domains. Study 2 additionally explored potential differences in how people make risky decisions on behalf of younger and older adult targets. Younger (age 18–35 years) and older (age 60–81 years) adults (as target persons of the risk evaluations) as well as informants reported on risk perceptions and the likelihood of risk-taking for health, financial, and social scenarios concerning the target persons. Congruence between self-rated and informant-rated risk perceptions and risk-taking were computed on a dyadic as well as a group level. Results: Informants’ risk perceptions were positively associated with the risks their partners perceived for themselves. Informants and their partners agreed that social risks vary little across adulthood, but they disagreed in terms of recreational, financial, and health risks, and in terms of the decisions they would make. Conclusion: Family members, partners, and close friends are sensitive to vulnerabilities of their social partners, but in some domains and according to their partners’ age they perceive a greater (or smaller) risk than their partners perceive for themselves. In situations requiring surrogate decision-making, people may decide differently from how their social partners would decide for themselves.