Summary: North America is a global center for native freshwater mussel diversity with more than 300 species. Mussels are among the most imperiled fauna on the planet. Reasons for both local and widespread declines in mussels are largely unknown, although threats can include habitat loss and fragmentation, disease, contaminants, altered flow regimes, invasive species, and climate change. Over the past three decades, there has been considerable research on mussels. Nevertheless, substantial information gaps are limiting conservation efforts. For example, we have limited data on status and trends, effects of emerging stressors, and habitat requirements for mussels. This talk will provide an overview of the current state-of-the-science on: (1) the status of mussels in North America, (2) ecosystem services provided by mussels, (3) how to define suitable habitat for mussels in large rivers, and (4) the effects of stressors on mussels. Through its diverse and strategically located workforce, long-term research focus, and management of large hydrological and biological datasets, the USGS is uniquely suited, and programmatically aligned, to address the broad scale multidisciplinary research needed to conserve mussels. To facilitate USGS’ efforts to conserve mussels, a Bureau Wide Strategic Science Vision for Mussels was recently developed. USGS research on mussels has provided relevant data, information, and tools to help local, state, federal, and non-governmental resource partners make informed decisions to support the conservation of mussels in large rivers.