Hand-stinging and mass exposure methods or rearing the parasitoid Cotesia flavipes Cameron (Hymenoptera: Braconidae) on the stem borer host, Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae), were compared. The proportion of hosts successfully parasitized, progeny production, proportion of female progeny, and host mortality did not differ between the two methods. However, there was evidence of superparasitism of mass-exposed hosts. Releases of C. flavipes as adults and as cocoons were both effective methods for field colonization of the parasitoid. A device for the release of C. flavipes in the cocoon stage is described.