When males ofTrichoplusia niwere continuously exposed to female sex pheromone, their pheromone-induced activity diminished more rapidly than it did for males exposed to repetitive pulses of pheromone. The males remained partially habituated for at least 15 min following many hours of pre-exposure to either the continuous supply or repetitive pulses of pheromone. When the males were continuously exposed and presumably habituated to pheromone throughout the night, there was no apparent effect on the timing of their flight or feeding behavior. An understanding of the behavior of male moths during and following prolonged exposure to sex pheromones may enhance man's utilization of the pheromones for pest control.