The mating behavior of the desert locust,Schistocerca gregaria(Forskal), was studied in the laboratory to explore the hypothesis that long-range communication signals may be operative in the solitarius phase. Before mating, males actively scanned the visual field, frequently cleaned their antennae and compound eyes, and jumped toward the females. The females, in response, moved slowly in front of the males and vibrated their entire bodies. Males assaulted and grasped the females, which at first tried to kick off the males using their hind legs but eventually submitted. In wind tunnel experiments with hidden females, males spent ≍33% of their time in searching and>80% were able to locate females, whereas, in the absence of the hidden females stimulus, they spent little time (<5%) in searching and remained in a resting state near the release point. In the presence of hidden females, the males also scanned and jumped more frequently, whereas they did not actively scan or jump in the absence of hidden females. When males were held in wire screen cages and females released downwind, the females did not respond to the males, indicating that males search for females when mating. Blinded males showed no interest in feeding or mate finding. Suppression of acoustic signals by gluing female wings did not significantly affect the male response. These studies affirm, for the first time, the emission of a sex pheromone by the solitarius females that attracts males.