none Emergence and mating of the braconid Apanteles flavipes (Cameron) were studied both in the field and laboratory. Both sexes emerged simultaneously usually within 2 hr after sunrise. Light played an important role in the commencement of emergence. The average time required for total emergence was 47.3 min. On emerging the adults did not immediately fly away, but remained on the undersurface of sugar cane leaves located within ca. 50 cm from the cocoons. The first copulation occurred 10 min after the start of emergence. Males exhibited polygamous mating, but females monogamous. The sex ratio of 1,570 adults emerging from 30 cocoon masses was strongly biased in favor of females. The insemination ratio of females attained 98.0% in the wild population.