Several authors have reported a faster immunological and hemopoietic post-transplant reconstitution using autologous peripheral blood stem cell (PBSC) than using autologous bone marrow stem cells. A large number of PBSC can be collected by leukapheresis during the hematological recovery after induction or salvage chemotherapy. In our experience we demonstrated that several separators, even if they have different results in mononuclear cell (MNC) yields, red blood cell and platelet contaminations, are able to collect PBSC for autotransplantation in patients with several malignant diseases and different status of disease. Eighty three patients were submitted to 590 leukapheresis procedures using 4 different blood cell separators: the results showed that all employed protocols are efficient in the collection of peripheral MNC even if after the widespread use of granulocytecolony stimulating factor (G-CSF) in the harvesting phase, the blood cell separator efficiency in terms of MNC is reduced. The use of GCSF in combination with other growth factors, during chemotherapy mobilization could simplify, in the future, this therapeutical program even if improvements in the efficiency of PBSC collection protocols are required.