Project Summary Abstract Researchers estimate an 832 percent growth in the number of Latinos with AD from 379,000 in 2012 to 3.5 million by 2060. While families frequently support the communication in people with Alzheimer’s Disease and Alzheimer’s Disease Related Dementias (AD/ADRD), language differences can create particularly complex situations for caregivers who must navigate a dominant English-language system for a family member who has reverted to their first language. This issue is particularly acute for Latinos, given that the majority are bilingual, and many families are (and will be) affected by complex caregiving needs. Frequently, the translation of materials serves to promote service access for linguistically diverse groups. But to reflect underlying cultural nuances and to identify the best secular phrasing and/or idiomatic expression in the target language, constructing valid measures requires more than mere translation. Moreover, because language is communal, it is closely tied to identity formation and acculturation, which can affect people’s social network formations and reinforce language skills. Arguably, analyses of valid measures should also consider how the social (linguistic) context might influence responses. We propose to enrich the National Social Life, Health, and Aging Project (NSHAP), a longitudinal study of older adults focused on social relationships, physical and mental health, cognitive, sensory, and motor function, and medication use. NSHAP oversampled Latinos, collected data in English and Spanish, and interviewed respondents in four rounds (2005-06, 2010-11, 2015-16 and 2021-22). However, these data have rarely been used to study Latino older adults’ health and social lives. No research has been conducted that compares the social networks of English- and Spanish-speaking Latinos and we know nothing about caregiving within these networks. NSHAP lacks questions on language usage in daily life and contains few questions on how language and cultural characteristics might impede access to health and other important institutions. To contextualize aging and family caregiving of AD/ADRD among Spanish- and English-speaking Latino older adults we aim to augment the NSHAP social network roster and caregiving questions, improve NSHAP Spanish-language measures of caregiving and social networks, and administer the enhanced NSHAP protocols to Latino AD/ADRD caregivers in Spanish and English.