The dramatic rise in antibiotic-resistant pathogens has renewed efforts to identify, develop, and redesign antibiotics active against the resistant bacteria. This review will focus on the increasing number of patents aimed at employing the potential of antimicrobial polypeptides i.e., the bacteriocins, in vetrinary medicine and human health. Bacteriocins demonstrate enormous possibilities in treating and containing target bacteria and may be a part of novel approaches for replacing classical antibiotics at a time when many pathogens are no longer susceptible to the existing antibiotics. We will review the new knowledge-based approach to the exploitation of these bacterial produced toxins to treat human and animal infectious diseases as well as inhibit the proliferation of eukaryotic cells i.e., treating tumours. The ability to develop novel bacteriocin-based-drugs aimed at potential target cells, prokaryotic as well as eukaryotic, may open new possibilities for the design of improved antibiotics possessing refined characteristics.