This data set consists of spoiled gradient-recalled echo magnetic resonance imaging data from five healthy volunteers (four males and one female) scanned twice at four sites having 1.5T systems from different vendors(Siemens, GE, Marconi Medical Systems). Some subjects were also scanned a single time at another site. One subject was only scanned twice at three sites (subject 73213384) and once at another site. For each subject, four Fast Low-Angle Shot (FLASH) scans with flip angles of 3, 5, 20, and 30 degrees were obtained in a single scan session, from which tissue proton density and T1 maps can be derived. These data were acquired to investigate various metrics of within-site and across-site reproducibility. This study was sponsored by the Brain Morphometry testbed (MBIRN) of the Biomedical Informatics Research Network (BIRN). The images have been defaced so that no facial features can be reconstructed from these data.