In this guidance document FDA provides recommendations to blood and plasma establishments, manufacturers, and testing laboratories that are implementing a licensed method for HIV-1/HCV NAT, on testing individual samples or pooled samples from donors of human blood and blood components for HIV-1 RNA and HCV RNA. This document contains recommendations regarding product disposition (§ 610.40(h)), and donor management (§ 610.41 and § 630.6) based on the results of NAT and serologic testing for markers of HIV-1 and HCV infection on samples, collected at the time of donation, from donors of human blood and blood component donations.