Plant parasitic nematodes (PPN) cause significant damage to a broad range of vegetables and crops, worldwide. Biological control agents (BCA) represent a promising approach to manage these dangerous organisms. A comprehensive overview is presented on fundamental mechanisms governing the interactions between beneficial BCA vs PPN, alongside exploring the diverse biological and molecular relationships crucial to mitigate damage in agricultural crops. Different nematicidal activities and their large-scale efficiency are also discussed. Finally, an overview is provided about most significant factors affecting the success or failure of BCA in a reliable strategy to control PPN.