Like all the phenomena that the human mind is knowledgeable about, the phenomenon of violence should be regarded as a complex macrosystem, where systems of networks and agents are linked and interact at different interconnected levels. This means that complexity refers to the phenomenon per se, to the various cognitive and emotional processes through which the human mind should examine and evaluate it and to the development of solutions to eradicate violence itself. It is clear that the complexity of these processes of examination and evaluation should be a requisite both of scientists and of laypeople. This does not mean that the scientist or the layperson should be knowledgeable about all the components and aspects of the macrosystem in their complex interconnections but that they should think and act on the grounds of their awareness of this complexity. One of the main issues relating to the study of violence is the definition of violence itself. In this respect, it is here suggested that thoughts and emotions, and not only behaviors, should be included in the definition of violence. As an exemplar of the difficulty regarding this specific issue, some considerations will draw on data obtained in a previous study on children and adolescents’ animal abuse experiences. It is also important to point out that complexity does not only refer to the explorations of the connections between systems taken from different research fields (e.g., neurology, biology, psychology, sociology, etc.). It can also refer, for example, to the theoretical premises of the research and of the questions at stake, to the scope and aims of the research and of these questions, and to the methods used in the investigation. In the same way, it is also important to bear in mind that, rooted in the theoretical premises and in the aims, are also specific views of society and life in general and that these views deeply and unavoidably affect the whole investigation process. It is clear that focusing on complexity also means opposing the fragmentation which usually characterizes the scientific study of violence and the interventions aiming to countervail it. Finally, as complexity theory indicates, through this “holistic” approach, a new conceptualization and understanding of violence could emerge so as to lead to more innovative and effective solutions to the problem of violence.