The book: level B (IUP - Bachelor's degree) Pesticides create pollution that spreads to groundwater and the contents of our food. They are harmful to health and detrimental to wildlife and biological balances. Additionally, the acquired resistance of some pests tends to render pesticides ineffective. Other sustainable solutions to protect crops are therefore necessary. Biological control is one such solution. It involves using living organisms or their products to combat other organisms considered harmful. The book focuses on protecting cultivated plants and farm animals against harmful arthropods (insects and mites) and weeds. It presents and analyzes various techniques, distinguishing between: - Biological control methods that do not involve the use of auxiliary agents: use of plant extracts, varietal control, sexual confusion, autocide control - - Methods that involve the use of auxiliary agents: microorganisms, phytophagous organisms, predators, nematodes, parasitoids.