Chemicals must be used to control the codling moth, Carpocapsa pomonella (L.), in most apple and pear growing areas throughout the world. Unfortunately, this practice has caused or contributed to greatly increased mite populations, decimation of many beneficial insects, insecticide resistance, soil poisoning, and other problems. Successful use of the sterile male technique against the codling moth would eliminate or alleviate a number of these problems. This technique consists essentially in the sustained over-flooding of the native population with sexually sterile males. The main prerequisites for its use include: (1) a method of inducing sterility or dominant lethality in the sperm without affecting normal behaviour or longevity of the male, (2) the released insects themselves must not be injurious or noxious, ( 3 ) the method of release should permit intimate mingling of the sterile males with the native population, and (4) the availability of an economical method of mass culturing the insect. Photographs illustrate how these prerequisites were investigated for the codling moth.