The Seroconversion Surveillance Project has completed 3 1 2 years of data gathering on the incidence of HIV antibody conversion in hemophiliacs. Data on 7214 patients treated at 125 Hemophilia Treatment Centers has been gathered and analyzed. Thirty patients were identified that seroconverted during this time period, and eight of them met the CDC criteria for seroconversion on clotting factor concentrates that had been treated to eliminate/inactivate contaminating viruses. None of the eight had been treated exclusively with concentrates that were made from HIV antibody tested plasma and had been treated to kill infectious viruses. At this time we conclude that the risk of HIV infection from currently available concentrates that are made from HIV antibody screened plasma is extremely low. An abstract was presented at the 1990 AIDS meeting in San Francisco and a manuscript is in preparation.