The single aim is to develop a system of meiotic genetic analysis for Dictyostelium discoideum. Dictyostelium has served as a model system for studying single cell amoeboid motility and chemotaxis and multi- cellular fate selection and regulation. The major limitation has been the difficulty in genetic analysis of this haploid organism. Dictyostelium has enjoyed a resurgence in recent years due the ease of homologous gene replacement to study a variety of cellular functions. In the wild, Dictyostelium has a sexual, diploid cycle. Unfortunately, the laboratory strains of Dictyostelium have lost this ability. Kessin proposes methods to establish sexual strains of Dictyostelium which will be essential for genetic mapping, isogenization of strains, and creating multiple mutant stocks.