Technical Abstract: This chapter treats several key aspects of rearing procedures for predatory bugs. The value of natural, factitious, and artificial foods for the major species used in biological control is reviewed. Whereas several types of factitious foods are routinely used in the production of heteropteran predators, the adoption of artificial diets in mass production systems has remained negligible. Special attention is given to the implications of zoophytophagy for the production of predatory bugs. The use of plants and plant materials as sources of water and supplementary nutrients, and as living and oviposition substrates is discussed, as well as the potential of alternative substrates. The impact of crowding and cannibalism and of the presence of micro-organisms on the performance of rearing systems is also addressed. Although important gaps in our ability to produce heteropteran predators are identified, equally important is that production will clearly benefit from new technologies that are rapidly expanding our knowledge of genetics, and developmental and reproductive biology.