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As classical biological control agents, egg parasitoids exhibit a greater rate of establishment than other parasitoid guilds, but have not been as effective in suppressing the abundance of the target pest. Mymarid introductions have provided the most spectacular results, particular in the control of invasive cicadellids and curculionids, whereas Trichogramma introductions have very seldom been effective. The success of augmentative biological control with egg parasitoids has been mixed, which highlights the need to know enough about their ecology and behavior to be able to select effective indigenous species, to mass produce them as a quality product at a competitive price, and to formulate and apply them effectively. Programs that combine egg parasitoid augmentation with behavior-modifying infochemicals or compatible insecticides are likely to facilitate successful adoption by end users.

Augmentative biological control, where natural enemies are periodically introduced, is commercially applied over large areas in various cropping systems worldwide. It is a popular biological control approach amongst professional and progressive farmers, and has been stimulated by the present international attitudes regarding reduction of pesticide use. Initially augmentative biological control was used to manage pests that had become resistant to pesticides. Now it is applied for reasons of efficacy and costs, which are comparable with conventional chemical control. Farmers are also motivated to use this form of biological control to reduce environmental impacts of pesticide use.