An original data collection effort is often conducted by a scientist or group of scientists representing a single discipline. While secondary analysis of that data may occur within the same field, researchers from additional disciplines may also become interested in the data as well, creating a diffusion of the data across disciplinary boundaries. This paper investigates this idea using datasets archived in the Civic Learning, Engagement, and Action Data Sharing project at ICPSR. We compare the disciplines of the original researcher(s) involved in a data collection to the disciplines of researchers who have published findings based on analyses of these same datasets. Our analysis shows how some data become utilized by diverse disciplines over time. The paper also describes the extent to which researchers collaborate across disciplines in producing and analyzing data. Finally, we examine whether characteristics of the data (such as the breadth of the data) lead to greater diffusion across disciplinary boundaries. We conclude by discussing the value of sharing and using archival data across disciplinary boundaries.