In Phase I antigenic peptide epitopes of HIV-1 p24 and gp41, and of HIV-2 gp34, were identified by synthesizing overlapping peptides representing the entire p24 and gp41 proteins of HIV-1, and portions of p34 of HIV-2, and by screening these peptides for antigenicity by immunoassay. The immunodominant peptides were utilized to develop reagents that detected antibodies to HIV-1 and HIV-2, and a rapid visual test was developed that requires no instrumentation and can be completed in less than ten minutes. Initial results indicate superior sensitivity and specificity of the peptide base assays, compared to currently licensed EIA and rapid tests for detection of antibody to HIV-1. Phase II funding will be used to identify key amino acid residues within each peptide epitope and to optimize these peptides for both immunoreactivity and stability, to prove feasibility in terms of GMP manufacturing requirements, and reproducibility, and to complete FDA regulatory interactions leading to an IND study for licensing of the peptide-based tests. If successful, these tests will provide superior performance to existing methods for the detection of antibodies to HIV.