Abstract Despite dramatic changes in family behavior in the U.S. over the last 150 years, local level marriage and divorce data over time are not available in analysis-friendly formats nor via Decennial Censuses. Therefore, spatial and temporal variation in how these marriage and divorce patterns operate are unknown. The objective of this proposal is to archive, document, harmonize, and disseminate nearly 150 years (1867-2010) of existing county and state-level administrative data on marriage and divorce. Administrative data are the only source of historical counts of marriage and divorce at the local level. These data exist in disparate formats including official reports, pamphlets, books, and websites. The rationale underling this project is that these resources are not available on a wide scale in useable formats (i.e. in conjunction with other county and state-level variables or in a GIS or statistical package format) and the effort for any one researcher to compile these data is too onerous, OR it is taken for granted that these variables are already available. Our approach will make these marriage and divorce data available in an existing database of other county and state-level data in analysis- friendly formats in conjunction with tools and resources for county and state-level analyses. Data sharing will be expanded by also disseminating data via interactive maps and infographics?further broadening the potential audience and impact of these important data. The expected outcome is innovative research that enables researchers to better understand and explain changes in family structure over a broad sweep of time and across the entire U.S. allowing them to address novel research questions about context. Research centers with specialized knowledge and established track records for reaching national audiences are ideally suited to conduct these activities, which places the National Center for Family & Marriage Research and Minnesota Population Center in a unique position to archive and disseminate this valuable set of historical administrative data not available anywhere else. These data and tools will fuel researchers to develop innovative ways of combining and using administrative and survey data. Importantly, this effort will serve multidisciplinary researchers including demographers, economists, geographers, historians, and public policy scholars who use geographic data as well as large household surveys. This project fits squarely with the PDB mission to enhance knowledge and data availability on families and households. The application is consistent with the purpose of the R03 mechanism and the program announcement to archive and document existing data to enable secondary analysis by a broad set of researchers.