Interactions between Steinernema scapterisci Nguyen & Smart and Ormia depleta (Wiedemann), introduced natural enemies of Scapteriscus spp. mole crickets, within hosts were examined by exposing mole cricket hosts to each natural enemy alone, both natural enemies simultaneously, or to one natural enemy 3 d before exposure to the other. Also, O. depleta life stages were exposed to the nematode directly (in water) and in sand. Host mortality was greatest (≥98%) when hosts were exposed to both natural enemies or when exposed to planidia (fly larvae) only. All hosts exposed to both natural enemies simultaneously and to planidia first produced nematode progeny; 79% of hosts exposed to nematodes only produced nematode progeny. When exposed to both natural enemies, fewer hosts produced fly progeny. From 10 to 31% of multiparasitized hosts produced progeny of both natural enemies. Adult fly eclosion from puparia developing in multiparasitized hosts was substantially less, but not significantly so, than eclosion from puparia produced in hosts exposed to planidia only. Development times for tachinids were shorter when developing in hosts exposed to planidia only. Nematode infective juveniles emerged sooner from hosts exposed to planidia first, but emerged more slowly from hosts exposed to the nematode first. Exposure to nematodes did not affect larvae as they exited hosts and formed puparia. Successful adult fly development and eclosion did not differ after exposure of fly larvae and puparia to nematodes directly and in sand. Adult eclosion from puparia formed from larvae exposed to nematodes in sand (79%) was less than that of puparia formed from larvae exposed to sand only (97%). A few pupae that had been exposed to nematodes as larvae were found infected with the nematode. No pupal infection occurred when puparia were exposed to nematodes. More than one-third (34.5%) of adult O. depleta were found infected after eclosing and crawling through sand containing the nematode. Because O. depleta appeared to be somewhat disadvantaged within multiparasitized hosts and larvae and adult flies were susceptible to infection when exposed to the nematode in sand, the potential exists for populations of the fly in the field to be adversely affected in areas where S. scapterisci is abundant.