Antimicrobial peptides (AMPs), are a family of host-defense peptides most of which are gene-encoded and produced by living organisms of all types. They have been extensively studied for more than two decades for their various roles in innate immunity, and their potential application as new antibiotics with new modes of actions. Although AMPs are believed to overcome bacterial resistance, there is emerging data for limited bacterial resistance. There are no constrains to the length, amino acid compositions and structure of AMPs as far as they preserve a net positive charge and a threshold of hydrophobicity which allow many of them to bind and permeate the microorganism's cell membrane as one of their targets. In addition to this microbicidal activity, recent studies have demonstrated receptor-mediated effector functions of several mammalian AMPs such as wound healing, LPS neutralization and chemotaxis. The 6th GRC on Antimicrobial Peptides will bring together an outstanding and diverse group of scientists at the forefront of this multidisciplinary field, who will address exciting topics aimed at advancing our knowledge regarding the roles of AMPs in innate immunity, as well as their potential application as innovative anti-infective agents to combat pathogenic microorganism in plant, animal and human, and as agents for potentiating immune responses.