Animal venoms are a complex mixture of bioactive molecules that have evolved over millions of years for prey capture and defence from predators. Animal venom consists of many different types of molecules, with disulfide rich peptides being the major component in most venoms. The study of these potent and typically highly selective molecules, has ultimately led to the development of venom-derived drugs for the treatment of diseases such as type 2 diabetes mellitus, chronic pain, hypertension and thrombosis. As technological advances improve, a large number of bioactive peptides have been discovered from a diverse range of venomous animals. Many of these molecules may have potential applications as molecular tools for understanding normal and disease physiology, therapeutics, cosmetics or in agriculture.