This chapter serves two purposes. First, it introduces the reader to computational criminology as a subdiscipline related to, but distinct from, digital criminology. Following a brief overview, the chapter proceeds with a discussion on why computational criminology is needed to advance the field of criminology. Concepts and ideas associated with computational criminology, including ethical and epistemological challenges of this project, are highlighted. As such, this chapter serves as a template, or roadmap, for students of criminology and practitioners considering research or applications spanning both the online and offline worlds, or otherwise interested in computational methods that can be adapted to criminological research. Second, this chapter also provides an overview of the methodological details necessary to understand the current mixed-methods case study, the results of which are presented in chapters “ Complexity, Similarity and Tie Formation in Advert Networks ”, “ Network Influences on Extreme Service Advertisement ” and “ Key Messages and Conclusions: Future Directions in the Computational Criminology of Internet-Mediated Exploitation ”. Some of the more technical details associated with particular methods are saved for subsequent chapters, whereas broader descriptions are presented here.