The emergence of resistance to existing antimicrobial agents is a pressing concern for human health. The effort in this regard has resulted in the identification of novel molecules which can resist pathogens developing resistance. One group of compounds explored for such novel properties are the antimicrobial peptides (AMPs). AMPs are an essential part of innate immunity that evolved in most living organisms over 2.6 billion years to combat microbial challenge. The therapeutic potential of AMPs is attributed to their membrane lytic properties. The peptides have demonstrated their ability to kill rapidly a broad spectrum of microorganisms including multidrug resistant bacteria, fungi and viruses. This book intends to make the reader aware of the synthetic AMPs and the possibilities that these compounds carry for discovery of newer and more effective antimicrobial agents.