Content reuse, defined as how often and in what ways digital library materials are utilized and repurposed, is a key indicator of the impact and value of a digital collection. Traditional library analytics focus almost entirely on simple access statistics, which do not show how users transform and remix materials found in digital collections. This lack of distinction, combined with a lack of standardized assessment approaches, makes it difficult to develop user-responsive collections or highlight the value of these materials. Developing a Framework for Measuring Reuse of Digital Objects, an IMLS-funded project (LG-73-17-0002-17) by the Digital Library Federation Assessment Interest Group (DLF-AIG), conducted a needs assessment of the digital library community to determine features of a future assessment toolkit that goes beyond use and traditional library metrics, and focuses on transformation. This presentation will provide an overview of the mixed-methods approach used to generate data, share the results of this project, and discuss next steps for implementation.