The mobilization and collection of hematopoietic stem and progenitor cells (HSPC) is central to many potentially curative treatments for cancer and some non-malignant conditions. Recombinant human cytokines have been the mainstay of therapeutic HSPC mobilization, particularly G-CSF. Even with currently used mobilization regimens using G-CSF with or without chemotherapy, up to 60% of patients can fail to mobilize enough HSPC for a transplant procedure. Recombinant human stem cell factor (ancestim, rhSCF, Stemgen) is another such cytokine, which has shown promising synergy when used in combination with G-CSF for HSPC mobilization. It provides a useful second-line option for prior failed-mobilizer patients and those who are anticipated to mobilize poorly due to recognised risk factors. It may also have utility in promoting bone marrow recovery in cases of refractory bone marrow failure such as aplastic anaemia and prolonged non-engraftment after allogeneic HSPC transplantation. We review the literature supporting the use of rhSCF in the context of HSPC mobilization and bone marrow failure. The emergence of other novel agents for HSPC mobilization such as plerixafor (AMD3100, Mozobil) will further demarcate the role of Ancestim as a second- or third-line mobilization agent for the mobilization-refractory patient.