Allogeneic transplantation of peripheral blood stem/progenitor cells (PBSC/PBPC) has been increasingly used as an alternative to allogeneic bone marrow transplantation. To mobilize and collect a sufficient number of PBSC/PBPC for engraftment after allotransplantation, granulocyte colony-stimulating factor (G-CSF) has keen preferentially used. The mobilization protocol, however, has not been fully established. In this review, dose and schedule of G-CSF administration, characteristics of G-CSF-mobilized PBPC products, cytokines other than G-CSF for PBSC/PBPC mobilization, and safety of the PBSC/PBPC donors are discussed for clinical application of allogeneic PBSC/PBPC transplantation.