Racial or ethnic minorities with leukemia who receive HLA-identical sibling hematopoietic stem cell transplants (HSCTs) are reported to have worse survival when compared with whites. Characteristics of US HSCT centers according to the proportion of ethnic minorities who undergo transplantation were compared to explore systematic differences among centers; the association with 100-day mortality was evaluated to determine whether center factors may explain the observed discrepant survival among ethnic minorities. One hundred sixteen US transplantation centers that performed HLA-identical sibling transplantations for leukemia were analyzed. We compared physician and health care provider staffing, transplantation unit procedure and resources, and medical center organization according to the volume procedure ratio of ethnic minorities who underwent transplantation and also according to the ratio of Hispanics who underwent transplantation. Centers that performed transplantation in a higher proportion of ethnic minorities were more likely to perform fewer transplantations per year, to have fewer devoted transplant beds, to be in an urban setting, to have a lower physician to patient volume ratio, and to follow up survivors 1 year after transplantation. Centers that performed transplantation in a higher proportion of Hispanics were more likely to perform fewer transplantations per year and to have fewer devoted transplantation beds, were less likely to perform outpatient transplantations, were more likely to be in an urban setting, and were less likely to have posttransplantation immunization protocols. Observed differences in center factors were not associated with 100-day mortality after adjustment for disease severity. Our results suggest that the inferior survival reported in ethnic minorities after HSCT may not be readily explained by center effects.