The United States Polar Rock Repository is a national facility designed for the permanent curatorial preservation of rock samples, unconsolidated material, dredges and terrestrial cores, along with associated metadata.   The facility was established by the Office of Polar Programs at the National Science Foundation (NSF), because the extreme cold and hazardous field conditions make field work costly and difficult. The repository provides, along with an on-line database of sample information, an essential resource for proposal preparation, pilot studies and other sample-based research that should make fieldwork more efficient and effective. This latter aspect should reduce the environmental impact of field work in sensitive polar regions. The USPRR also provides material samples for educational outreach.  Rock samples may be borrowed or used for research, educational or museum use.