Since being accidentally introduced into East and West Africa in the late seventies, the Larger Grain Borer (Prostephanus truncatus) - abbreviated to P.t. - has caused major losses in farmers' stores of maize cobs and cassava chips. Biological control of this stored-food pest constitutes an important contribution to the ecologically-sound and sustainable reduction of post-harvest losses. This publication outlines the major points to be borne in mind in this context. For more detailed suggestions, the reader is referred to the booklet "Recommendations on the use of Teretriosoma nigrescens for biological control of Prostephanus truncatus", available from the GTZ. Biological control of P.t. is achieved using a natural enemy imported from the pest's home country. The species in question is the predatory beetle Teretriosoma nigrescens (T.n.) of the family Histeridae. Following investigations into the efficacy and specificity of this species in its region of origin, and in laboratory tests in the Federal Republic of Germany, this beneficial organism was exported to Africa. There, further tests were carried out under quarantine conditions, before T.n. was released with the approval of national and international agencies. All the tests had demonstrated that, under controlled conditions, T.n. is capable of significantly reducing P.t. populations. The first release took place in 1991 in Togo, followed by Kenya, Benin, Ghana and Guinea. The predator is highly host-specific, as it is lured by a pheromone of P. t. when in search of its prey. Consequently, it poses no threat to beneficial species. Neither does it cause stored-food losses. In view of the positive properties of T.n. as an antagonist of P.t., its release is recommended to those countries of Africa where P.t. occurs.