In vitro rearing of entomophagous insects (IVREI) can be conducted with two main aims: firstly to develop an efficient tool for researches on insect biology, physiology, and behaviour, secondly to mass-produce insects for applied use. It was conceived in the 1940's, but really investigated from the 50's. Several teams, including less than one hundred main researchers, distributed among about a dozen countries, were implicated in these investigations. Hymenoptera, Diptera, Rhynchota, and Coleoptera are the principal orders of insects studied. The best results were obtained with egg or pupal hymenopterous parasitoids, tachinid larval parasitoids and some polyphagous predators. The future research structures will need the constitution of national or supra-national consortiums between public and private institutions to share financial means and research teams. The species that are expected to be developed in artificial conditions for biological control are on one hand species-specific parasitoids to reduce unexpected side effects, and on the other hand, polyphagous predators to simultaneously control several pest insects. The future of the production will go through more automation and quality control, to reduce the costs of the insects produced and guarantee reliable efficiency. To reach these objectives, the investigations need development towards innovative tools to define more adapted diets and to find new efficient quality criteria.