Summary This infrastructure proposal aims to further advance capabilities in the social sciences (broadly defined) to collect data on the daily lives of U.S. families and individuals. These data will be more accurate, more granular, and more comprehensive than is currently possible in traditional survey-based research. The context for this is the Understanding America Study (UAS), the probability-based Internet panel we have been building at USC since 2014. The infrastructure includes the combination of many data types (including survey data, information from wearables, contextual and administrative linkages, ecological momentary assessments, self-recorded narratives, and electronic records of financial transactions), as well as an open communication with the wider research community both in data dissemination and in soliciting input on content and methods. The UAS currently comprises about 10,000 U.S. residents, recruited by address-based sampling and provided with Internet-enabled tablets if needed. Surveys are conducted in English and Spanish. For the coming project year, we propose to expand the UAS national sample to 12,600 respondents, with oversamples of Blacks, Asians, and Hispanics, and sufficient representation of rural areas. Our project aims to create and make available to the research community a uniquely detailed and focused collection of information on U.S. households and individuals. To achieve this goal, we aim to strategically integrate selected external data sources with UAS survey data and expand the already broad set of topics covered by UAS surveys.