The present invention is directed toward methods for the production of non-infectious, replication-deficient, immunogenic human immunodeficiency virus (HIV)-like particles. These particles are prepared from a recombinant expression vector comprising a heterologous promoter operatively connected to a DNA molecule comprising a modified HIV genome devoid of the long terminal repeat (LTR) regulatory regions but containing at least the gag and pol genes in their natural genomic arrangement. This vector is introduced into mammalian cells to produce the particles of interest. These particles should prove useful in a number of diagnostic, virologic, and immunologic applications.