Auto-SCT has been shown to be a potentially curative treatment for a variety of hematological malignancies. Auto-SCT is dependent on the successful mobilization and collection of hematopoietic stem cells to ensure engraftment. The inability to mobilize sufficient number of hematopoietic stem cells using standard cytokine-assisted mobilization strategies excludes eligible patients from potentially curative auto-SCT. Plerixafor (AMD3100; Mozobil), a novel bicyclam antagonist of the SDF-1α/CXCR4 complex, has been reported previously to augment PBSC mobilization in patients undergoing their first planned stem cell mobilization and collection attempt. In our experience, 17 of 20 patients otherwise eligible for auto-SCT who failed previous mobilization attempts had successful mobilization of CD34+ hematopoietic stem cells with one apheresis procedure, and an additional patient required two aphereses procedures, when treated with the combination of plerixafor and G-CSF on a compassionate use protocol available at our institution.