Biological pest control refers to the use of living organisms to suppress pest populations, making them less damaging than they would otherwise be. In agriculture and allied sectors, it is an essential component of sustainable crop production and integrated pest management. Unlike chemical pesticides, biological control relies on natural enemies and ecological processes to regulate pest populations, thereby reducing environmental pollution, pesticide residues, and resistance problems. The various biological pest control methods can be broadly classified into the use of predators, parasitoids, pathogens, and other biologically based techniques such as sterile insect technique and conservation of natural enemies. Predators are free-living organisms that consume a large number of prey during their lifetime. They play a vital role in controlling insect pests in field crops, horticultural crops, and plantations. Common predatory insects include ladybird beetles, lacewings, praying mantids, dragonflies, spiders, and predatory bugs. For example, ladybird beetles feed on aphids, whiteflies, and scale insects in crops like cotton, vegetables, and fruit orchards. Chrysoperla species, commonly known as green lacewings, are effective against aphids, thrips, and mealybugs. Predatory mites such as Phytoseiulus persimilis are used in greenhouse cultivation to control spider mites. In rice fields, spiders help in reducing populations of leafhoppers and stem borers. These predators are either conserved in the field by reducing pesticide use or mass-reared and released to augment their population. Parasitoids are insects that lay their eggs in or on the body of a host insect, and the developing larvae feed on the host, eventually killing it. Unlike predators, a parasitoid usually requires only one host to complete its life cycle. Egg parasitoids, larval parasitoids, and pupal parasitoids are widely used in agriculture. Trichogramma species are among the most popular egg parasitoids used against lepidopteran pests such as stem borers in sugarcane and rice, and fruit borers in vegetables. Bracon and Apanteles species parasitize caterpillars, while Telenomus species attack the eggs of certain crop pests. These parasitoids are mass-produced in bio-control laboratories and released in fields at specific intervals to coincide with pest egg laying. Their use has significantly reduced chemical pesticide dependence in crops like cotton, maize, and sugarcane. Pathogens used