The emergence and rapid horizontal spread of antibiotic-resistant traits in bacteria of human and veterinary clinical significance has been a driving force in the search for new classes of antibiotics. Recent studies have shown that AMPs (antimicrobial peptides) potentially have a role in addressing this problem. These AMPs are produced naturally by a diverse array of organisms, including bacteria, plants, insects, fish and mammals. Given this diversity, researchers trying to perform comparative studies on AMPs are likely to encounter difficulties in obtaining workable quantities of peptide. Such studies are required for optimization of antimicrobial activity, product stability, mode of delivery and industrial-scale production, and are vital if these peptides are ever to be brought to the market. Recombinant expression of AMPs is one hope for producing suitable amounts of diverse peptides. Here we review the literature regarding microbial heterologous expression systems for the production of recombinant AMPs.