Several species of the genus Cicadulina are vectors of maize streak virus (MSV) (Rose, 1978). This virus causes maize streak disease, a disease that is of great economic importance in sub-Saharan Africa (Geddes, 1990; Vogel et al., 1993). Despite a large body of research on the biology of Cicadulina spp. in Africa (Rose, 1978; Okoth et al., 1987a, b), little is known about their mating behavior, in contrast to that of other leafhopper genera (Saxena and Kumar, 1984; Heady et aL, 1986; Hunt et al., 1992; Claridge and de Vriejer, 1994). The present investigation was undertaken as part of a wider study of the vector ecology of Cicadulina spp. in Uganda. Cicadulina mbila Naud6 and C. storeyi China were studied because they are among the most efficient transmitters of MSV (Dabrowski, 1987; Asanzi, 1991) and because they are among the most abundant leafhopper species in several African countries (Rose, 1974; Okoth and Dabrowski, 1987), including Uganda (W. W. Page, personal communication). The study sought to establish whether substrate-transmitted vibrational signals were produced by C. storeyi and C. mbila during mate location, to make visual observations of matings, and to determine the age of onset of sexual behavior and whether either sex mates more than once.