Although committed progenitor cells have been harvested during the standard plateletpheresis, only few experiences were specifically carried out in normal donors. The major drawback is the very low number of circulating haemopoietic stem cells and, besides a donor manipulation, a good harvesting technology is a fundamental prerequisite. To verify the effectiveness of an automate system, twenty normal volunteer donors were randomly assigned to four protocols of simultaneous PBSC and platelet collection. A Baxter separator CS 3000 was employed and we compared the yields and the efficiency of the modified Program 1 plus isoradial chamber (Protocol A), the modified Program 1 plus granulo chamber (Protocol B), the standard Program 3 plus isoradial chamber (Protocol C) and the standard Program 3 plus granulo chamber (Protocol D). The absolute yields for WBC (x10(9)), MNC (x10(9)), platelets (x10(11)) and CFU-GM (x10(4)) were respectively: 10.4, 10.1, 6.5 and 29.5 for Protocol A; 10.1, 9.9, 5.2 and 14.7 for Protocol B; 10.0, 9.9, 5.2, 14.7 for Protocol C, and 12.7, 12.4, 6.8 and 57.4 for Protocol D. The best CFU-GM efficiency was achieved with Protocol D (33%) vs. Protocol A (27.5%), Protocol B (14.5%) and Protocol C (27%). The above differences, although remarkable, were not statistically significant. Though preliminary, this study demonstrates the feasibility of a combined platelet and PBSC collection in normal donors.