Antimicrobial peptides are gene-encoded molecules first discovered for their microbicidal properties but recently shown to have pro- or anti-inflammatory functions. Their role as immune regulators is being expanded with evidence that some antimicrobial peptides stimulate keratinocyte migration, proliferation and cytokine or chemokine production. Poorly named, antimicrobial peptides are multifunctional pillars around which the innate and adaptive immune response has evolved.