The discovery of hybrid sterility in male progeny from crosses between Heliothis subflexa (Guen‚e) and H. virescens (F.) and encouraging results of population suppression by this sterile trait has stimulated research for hybrid sterility in H. zea (Boddie). Since the sterile trait was found for H. virescens, development of a similar one for H. zea by crossing it with a closely related species seemed-possible. Exotic Heliothis species were imported into the Stoneville Research Quarantine Facility and evaluated for hybridization and sterility. Crosses between H. armigera (H�bner) females, from India X H. zea males produced hybrid progeny of which both sexes were fertile. There was mating but no reproduction from H. punctigera (Wallengren) females from Australia and H. gelotopoeon (Dyar) females from Argentina X H. zea males. Studies with H. armigera conferta (Walker-3 from New Zealand and H. armigera and H. letcheri (Hardwick) females from Africa mated with H. zea males are incomplete but progeny with fertility in both sexes have been produced. These studies will continue with these and other Heliothis importations in search of hybrid sterility for H. zea.