The purpose of this paper is to examine the claim that the actions of those animal rights activists willing to use violence in the pursuit of their cause constitutes terrorism. Although there is no generally accepted definition of 'terrorism' ,1 there is, however, a high degree of consensus as to the core characteristics of the phenomenon. These characteristics include the use or threat of use of violence, the existence of a political motive, target selection is symbolic, the goal is to modify behaviour, the methods employed may be extreme, the aim is to terrorize, and the act of terrorism is an act of communication.2 This paper will provide a brief recap of the animal rights position, before concentrating on those groups willing to use violence, namely, the Animal Liberation Front (ALF), the Animal Rights Militia (ARM), and the Justice Department. These groups will be analysed in terms of their origins, aims, finance, strategy, tactics and organization in light of the core characteristics of 'terrorism' outlined above.